In fairness to Larian, performance issues should be lower priority since most people have workarounds (lower graphics settings, lower resolution), whereas those with crashes, conflicts or game-breaking bugs do not.
But in equal fairness the game should not have been released with this many widespread crash reports and performance issues in the first place. They could not have been unaware of these issues prior to launch and thus have no excuse as to why they exist post launch other than that they took the game out of beta too soon.
