The popular public worlds are like going onto AOL general chatrooms when those were popular. You get a lot of random people sticking around and often some obnoxious people. It's possible to find good conversation buddies and friends through them but it takes a lot of hopping between public worlds.

The real magic is when you either A) have friends who are already into it invite you directly to worlds with them and their friends, or B) find the niche public worlds that have a more mature and invested userbase. (Sadly, a lot of the niche worlds aren't compatible with VRChat on the Quest when running in standalone mode; you have to connect the Quest to a computer to get the full experience.)