Regardless, the remaster appears to have been rushed out due to increasing leaks, no? It's hard to believe that with the technical issues the release was actually intended to land in April 2025, instead of fixing issues until March 2026 and releasing it as an anniversary remaster.
Bethesda is notorious for buggy software releases. They could spend 10 years on something and it would likely have tons of bugs still.
0: I recall reading somewhere that the game uses a really old version of Bethesda's proprietary engine too - but only for physics.