In WOTR the Azata spellbook - the second most popular mythic path - wasn't fully implemented until a full calendar year after release. You would plan out your strategy, use the spell, lose the spell slot and nothing happened. Nothing. 3 of the spells that actually worked were implemented in ways that didn't work. The lich path - 4th most popular couldn't completed.
And yes the super vavakia as you mentioned.
The true ending - which takes a great deal of effort - couldn't be completed and it took ~6 months for them to release hints on how to complete the game without using a datamined guide. Before then you completed research on how to get the true ending and go the message "objective complete" Uh. Thanks? When I am supposed to show up at threshold again?
I could go on, it was absolutely unacceptable. I had the BG3 save file error but when I disabled mods it went away . . . I hate that WOTR has become my favorite game
I wasn't using mods. Neither was the Eurogamer reviewer that we have to thank for telling Larian about it. The problem was apparently the file was too big?
The super vavakia, also Mephistopheles and IIRC Nocticula was AWOL for a while there too. Buuut in comparison, it's not like Act 3 had everything at a bare minimum of working either. The fireworks quest and the dragon broke
hard for me, dialog and companion bugs were everywhere (and Gale and Minthara are still buggy), Ethel liked to be actually unkillable, the quest journal wouldn't update so you had to reload from your last save before you started the quest you were on, AI would 'hang' in combat if you were stealthed, sometimes indefinitely and I think the stealing system can only be called 'working' very charitably right now. Not counting PS5 only bugs like the super lag they had or game breaking multiplayer bugs.
When you compare that WotR was Owlcat's second game with a starting budget of 300k with a cap of 2 mil, seeing BG3's bugs raises an eyebrow. It being praised as 'polished' or 'finished' raised the second. And personally speaking, every big patch introducing a problem with saving for some people raises both eyebrows even higher. So in the end, I'd say the difference is the speed of fixing, which is wholly different from releasing playable.