For me the main problem is that going out for lunch in person with coworkers (even ones from other departments I've never met) is completely fine and I like to do that (when I was in the office I did that 3-4 days per week) but when I am having lunch at home I don't like it at all. I can't put my finger on it but it always feels like useless smalltalk and not making any connection where in person that works quite well. And I'm neither pro-office or anti-WFH or even someone who doesn't make friends online... but going out for lunch or a beer or just an afternoon coffee break is something that I can't reproduce via video/audio.