> eating animals will eventually be considered immoral. This is an extreme stance at the moment (hello PETA)
There are a lot more vegetarians and vegans than just PETA. It looks like around 5% of the US and hitting 10% in many countries (https://en.wikipedia.org/wiki/Vegetarianism_by_country). Many parts of India have very high vegetarian rates.
> How long will it be between the introduction of lab-grown meat until killing animals for food is banned?
I doubt that it will be about banning animal meat anytime soon. However, I think we might see many countries start to tax the environmental cost of meat which will make it quite expensive. This is unlikely in the US, but I could certainly see it in many countries whose politics are different.
> Will we get to the point where statues of now-famous people are pulled down because they ate animals? Assuming some variant of "cancel culture" exists then
I think this isn't a useful thought right now and just feeds into the "cancel culture gone mad" ideas. Few people have been canceled. Yea, Harvey Weinstein has been canceled...for rape. Kevin Spacey has been canceled...because of sexual assault against underage boys. Most people who seem to complain about being canceled are sitting on Fox News taking home giant paychecks. Tons of people encouraged riots at the Capitol and are making millions off it.
Yes, at some point in the very distant future, we might decide that killing animals for food isn't an acceptable behavior. A hundred years ago, a man couldn't be guilty of raping his wife. 200 years ago, a lot of people owned slaves. 60 years ago we had racial segregation. 40 years ago, it was acceptable to say that gay people deserved to die from AIDS. Things change.
But it's not like it's going to happen overnight. It's not like 2017 came along and Harvey Weinstein was like, "omg, is rape wrong now? Things change so quickly and I didn't know!" Attitudes will probably change over decades or centuries.
Like, we've spent hundreds of years getting to the point of "Black people are equal and you shouldn't be racist" and people still often aren't getting canceled for racism. I've seen posts of police officers covering up explicitly racist tattoos saying that in the current climate they feel like they need to be careful. It's been over half a century since the Civil Rights Movement, but now they're like, "oh, I guess I might get in trouble for being explicitly racist in a position of power." The idea that someone would be canceled for eating an animal in our lifetime seems unlikely. It certainly won't happen as some surprise.
> Will we see clever re-interpretations of religious texts dealing with the eating of animals?
In Judaism, a lot of people hold the belief that we won't eat animals in the messianic era (when the messiah comes). People are only allowed to eat animals because Noah saved them from the flood. Before the flood, people weren't allowed to eat animals. Part of the messianic era is that it's supposed to be how the world is meant to be.
This idea isn't a left-wing Jewish idea either. I would note that it's not widely known in the Jewish world and usually more known by orthodox people who do eat meat. Judaism often has a lot of things that might be a little less official, but nonetheless have some weight and resonance.
I think we also see some of this in Christian stuff. I feel like Christians like Isaiah 11:6's "the lion will lie down with the lamb" (yes, I know that technically that's not quite the animals in the text, but it is how I often hear it said by English-language Christians). I think the idea that predators might not be predators in some world-to-come isn't something that has to be creatively reinterpreted.
> Will we get religious divisions between different interpretations?
Yes. I mean, we have religious divisions over really tiny things. This is certainly larger than a lot of religious divisions we've seen.
> Will some people refuse to accept the general moral stance on eating animals because their religious text says it's acceptable?
Do religious texts say it's acceptable? Jewish texts certainly do - and they have a lot to say on how. However, rabbis have modified it over the centuries. Chicken was once acceptable to eat with dairy and now it isn't. I think the big thing for the Jewish community would be that many rabbis would say that lab-grown meat is more in the spirit of how we're supposed to live combined with the fact that it's likely to be so much cheaper than kosher meat tends to be. Given the likely price difference, even people who might be in the "it's fine to kill and eat animals as prescribed" are likely to be buying the lab-grown meat simply because it will make meat accessibly priced. In fact, chicken was deemed to be "fleishig" so that people could have an affordable "meat" for Shabbat meals (the category of "meat" from a Jewish perspective is slightly different from "animal" and doesn't include fish...it's a long story outside the scope of this comment). I think Judaism also evolves around community standards that do change. The Bible condones all sorts of capital punishments, but the rabbis rid the religion of them all a long time ago.
I can't really speak for other religions, but if lab-grown meat becomes available at a cheap price, has better food safety than the current system, can offer better consistency and taste, and causes slaughtered-meat to become niche and a lot more expensive...even if you don't have qualms about killing animals, do you want to pay for it?
Manufactured goods are so cheap because we can manufacture them. Growing animals is hard. It requires a lot of labor, a lot of land, a lot of water, a lot of carbon emissions, a lot of food, etc. I'm sure there will be some market for "real" meat for a long time, but it will likely get expensive. Manufactured meat is likely to get pretty efficient and cheap.
I think it's less about whether religions will continue to support killing animals and more about whether anyone will want to pay for it. "Hey, here's this $1 lab-grown burger that you know will be consistent and delicious and here's this $20 bespoke cow-slaughtered burger." The fact is that most people aren't going to want to pay a premium for the cow-slaughtered burger.
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Personally, I'm a vegetarian and have been for 15 years. I'm also Jewish. One thing I will note as a difference between semi-religious Jews and non-Jews is the difference in meat consumption. Many Jews, even if they aren't that religious, still won't mix meat and dairy and many won't eat non-kosher-certified meat. I have lots of friends who haven't been to a religious service in years, but still kinda do this out of a certain cultural thing or inertia. One of the things that this means is that they often don't eat meat with most meals. Meat is something they eat 2-4 times per week. By contrast, I'll have lunch with non-Jews where burgers, pizza with meat toppings, salads with chicken, etc. are the norm. Meat is a part of almost every meal.
The difference isn't a moral one: my non-vegetarian Jewish friends don't think eating meat is wrong. Eating meat is simply inconvenient and expensive for them. So they eat meat with a minority of their meals. The fact is that it's likely that slaughtered-meat will become expensive and inconvenient compared to manufactured-meat. Taco Bell or your local pizza place isn't going to spend a lot more money on slaughtered-meat if they can get a wonderful, consistent product at a cheaper price.
Regardless of whether slaughtered-meat stops being a thing or not, it will likely become a much smaller part of people's diets. This will be very important as we deal with global warming. Even if you're the type of person that's like, "I will always love a real steak on a grill and that's going to be every Saturday in the summer," the fact is that you're likely to also be eating a lot of lab-meat when you grab something at Burger King or getting deli-meat for sandwiches.
I think people like thinking about "zero", but for me lab-meat is about the 90% of "well, I just wanted some meat texture and protein in my meal." I'm hoping it'll take off and we'll see a huge reduction of our dependence on slaughtered-meat and the environmental impact it causes. I think it'll take time, but I think it's hard to bet against manufacturing efficiencies.