It's either disingenuous or just plain ignorant to set the bar at objectively wrong
The bar for what? If you mean the bar for a good explanation of what morality is, then the conclusion that it's an objective feature of the world is certainly not necessary.
or to imply that everyone thinks it's fine to have pets/eat animals
Come on, there is obviously a tiny minority of people who don't think that. Just like in the Muslim countries, there is a tiny percentage of non-muslims. Majority, however, have conformed to what is accepted by people around them. Same with views on slavery of non-human animals today.
or that aliens would follow our ethical guidelines.
Hmm, what is 'our ethical guidelines'? If emotivism is true and if you look around you and throughout the history, there are no 'our (human) guidelines'. For almost any moral issue, there will be people who like it and those that don't like it.
Neither moral universalism nor realism have a dominance in the philosophy of ethics.
I don't care what is currently popular in academic philosophy. There are many views in ethical philosophy, so it's unlikely that any of them will be the dominant view. Emotivism seems to be a good description of what moral sentences actually are. You have to differentiate between 'what moral sentences actually are' and 'what people think they are'. So, it's possible to say that emotivism/nihilism is true, while at the same time say that most people think that moral realism is true.
It's like you worked out that the emotivism that most people use for their moral compass isn't exactly well thought out, googled some phrase sceptical of ethics as a whole, found nihilism, potentially with a detour through scientism, and then burrowed down that rabbit hole without considering any other established school of thought.
People don't use 'emotivism' for their moral compass, since most people don't even know what it is! How can ethical views and theories influence moral compass of regular people?
Your reference to nihilism is very typical. Most people use it almost as an insult. There are strong religious and political interests in society and nihilism bursts their bubbles and questions fundamental assumptions, so the way they cope is by contaminating the word and using it as an insult.
Any response short enough for anybody to bother writing is going to need to take a whole bunch of premises as givens and rely on definitions for words you don't agree with.
haha then there is no point in replying. If you're going to redefine words and make arbitrary assumptions, then why bother talking about anything with anyone?
It'll just keep leading to chains of posts like this where you just keep asking stupid comparison questions like you're some form of internet Socrates, and being pleased when people don't reply adequately, or at all, because you're the one with the negative claim and consider anything other than a full argument from them as a default win for yourself.
This really ends with insults. You're labeling what I wrote as 'silly' and 'stupid' and trying to insult me by saying I'm wanna be internet Socrates. You've hit rock bottom with the insults.