it seems to me that anyone who's played ttrpgs long enough has some horror story about a player who ended up part of the group for too long and really spoiled the fun for people, so I don't think it's a given.
I fail to follow ...
If everyone have some simmilar experience, how it can be "not given" ? o_O
Anyway ... w/e man, play with whoever you want ofcourse, that is none of my busines ofc.

Im just saying that if i will play BG-3 in multiplayer, and will meet a group that will be unable to agree on HOW they wish to play ... i will rather keep searching.

Ours is a professional curated discord that pulls people that are good at working with others and we provide guidelines on what you might want to discuss before starting the game.
Mods are a non-issue in multiplayer mostly because all players would have to agree to the same mods before play began and that is a tall order. So we just have to build around what Larian plans to do in final release for multiplayer.
I think the concept of rolling or point buy starts with what kind of game you are playing. In an RP run you would be able to make a better case for rolling stats to inform the RP. A murderhobo run isn't a serious run so probably nobody cares there. However a serious run, or an Ironman run would probably be point buy because you want your run to have integrity.
I would really like a heads up so we can prepare but it sounds like we are going to have to just wait and see.