Things that break the game are the only things that are considered bugs to be hotfixed from what I can tell.
For example, if you had saved the Tieflings and had the party with them, but from then on everyone would think you destroyed the Druid Grove and you'd find no Tieflings at Last Light Inn because of that. Or if you save Nightsong, but when you come out of the Shadowfell you find Last Light Inn succumbed to the shadow curse with Isobel, Jaheira and all residents either dead or walking around cursed and everyone acting like you killed Nightsong. Other things could be (parts of) combat not working as intended, like specific skills doing unexpected amounts of damage, being unable to perform actions while you're not paralyzed or restrained in any other way, etc. Beyond that, they won't be making any more changes to the game.
With BG3 having had the last update and being in maintenance mode though, even some actual bugs are still in the game after months. I made a thread about a
bug with Lyrthindor's encounter, something that's been around ever since the Patch 8 stress test in January. It's been widely reported and talked about, like
here,
here,
here, and
here. I got a "Thank you for your report, this issue is known and may be fixed in a future update." as response to my bug report, but considering the bug has been around for 11 months now, I don't expect a hotfix to come anytime soon for anything being reported.
