It is not necessarily being around other people that bothers me, it is the things that goes along with going into an arbitrarily chosen building.
If work starts at 8, I want to be able to sleep until approximately 7:55 and still be on time. I want to make the most use of time that I allot to things as is reasonably possible.
I don't want to feel self-conscious about how I look, what I'm wearing, or how my body or breath might smell - it's not that I don't manage those things, it's that I don't want to have to worry about those things.
I don't want to sit in a place that does not feel like my own. Sure, I can hang up funny cartoons or bring in my own mug or whatever, but if I want a better chair? Gotta get the company to buy it. Want a needlessly fancy desk? Too bad. Wish there was better lighting/less harsh lighting in your work area? Gotta go to facilities - they might do something about it, if they are allowed to do so.
There's also practical things like not having to worry about someone accidentally eating my food, or having to clean up the coffee area because someone else was in a rush, or didn't care.
It also seems like meetings are at least a little bit more purposeful. It's harder to setup meetings online than in person, so it seems like a little bit more thought is put into them, when they do come up. Having everything recorded also helps me refer to it later, if needed.
About the only significant change from working in-person is that I tended to get considerably less work done when I was in-person. I don't know if I would measure higher productivity from WFH as strictly a "good" thing. I think that socialization has its merits too. I always viewed things like birthday parties as a meaningless distraction, but, I also wasn't going to cry about getting paid to eat a small amount of candybread for a few hours. I didn't really enjoy those things, but I could appreciate that others enjoyed it.
I get the desire for comradery, I'm not saying it doesn't serve a purpose, however, I can't help but feel that office comradery is arbitrary and forced. A kind of "You are required to be friends with this person. NOW!" Most of the people I work with are people I would never choose to actively hang out with outside of work - nor would I want to do so. We don't share interests the majority of the time, and that is what I prefer. They are, in large part, a stranger. I do not wish to know more than that they are competent at their job, and do not do things to make my own job harder.
There are people I make a point of seeing in a social setting, and there are people I am required to interact with in a professional setting. I do not think it is appropriate to mix business and friendship. It isn't that I treat work-people like robots, but rather, I have a workplace decorum, and a social decorum. I do not reveal the unprofessional side to professional people, and vice versa. The environment of each calls for different sorts of interaction. I cannot respect a boss who I have seen weeping into a pitcher of beer. The idea of drinking with people I work with is something that I just find incredibly repulsive. Maybe that's not the right word for it, it puts a kind of sickness in my mouth I can't describe; it's like watching pornography with your parents.