The problem, to me, isn't peoples curiosity or attempting to broaden their horizons. I think the outcomes of this are largely good; it encourages discerning people to exercise caution and makes for good light conversation. Where things get off the rails is when people believe their tentative research or association with a domain makes them authoritative in some sense.
I read the same waffling about masks you did, the information I read (since it was inconsistent) led me to believe that I should wear masks more than directed. I did this out of an abundance of caution because at the time early research eerily concluded that not much is known about the longer term effects of this virus, there was stark contrast in the symptoms various people had, and that there were layers to exercising prevention. I acted in a similar manner when I limited my social circle.
The difference in the way, I think, these people used much of the same information that I did is that it became authoritative to them. After they'd read enough articles straight from the CDC it made them feel qualified to interpret them. I'm reminded of one guy who demanded I get another PCR test before he hung out with me, even after I hadn't experienced a fever for 10+ days. For some context, when I got sick I came back negative on both tests I was given. I was later told my viral load was not high enough on those days, ironically these also happened to be some of the worst days of the virus. It was only after I lost taste and smell that the doctors realized I had COVID. My friend cited all the reading he had done as evidence that I just wouldn't accept his "perspective". When I asked the doctor about getting both PCR and an antibody test she responded, "Do you have an actual reason? We already knew you were sick." In reality, the time which I would've been contagious had long passed, yet my friend couldn't get it out of his mind that transmission was a possibility.
Another example is a friend whose brother had gotten COVID a few months back. His symptoms were certainly worse than mine. Where I didn't experience much trouble breathing, he did among other things. I went on a walk one day because it was one of the days in between being sick that I had some energy and wasn't overcome with brain fog. I shared that I was exhausted after this short walk and that I'd probably stave off a walk for a few days to see where I was at. She chastised me for going on a walk, explaining that her brother had been told not to exercise for three to six months, and that it seemed as if I was taking COVID as a joke. What I realized after googling this specific treatment plan is that it's usually given to people with some form of cardiomyopathy and other conditions (none of which I have.) I am now about 3 weeks removed from having COVID and I'm back to riding my bike, which is consistent with what my doctor told me. My doctor told me recovery has a lot of variables and I'll need to go at the pace that I'm comfortable with and listen to my body. Regular checkups should help to that end as well.
The theme among these people is when I tried to explain what doctors had told me and why I was going to stick to what they were saying (more generalized as drawing boundaries) I was met with harsh rejection. The key here is that authoritative sources were no longer respected. The fact of the matter is that doctors do take a bit to arrive at consensus and that can be frustrating to a public opinion that is waiting on them for their own sanity, but just because you landed on the correct conclusion a couple times (or even a more conservative solution that kept you equally safe) does not make you an authoritative source. So, I'm not going to tell people to stay in their own lane but you can't just go lecture people based on your own understanding. That's when you forget that all of this information you gather outside of your own domain is good for exercising caution and light conversation.