So I've played for 100+ hours just to get stuck on one of the last cutscenes. For some time I've experienced loss of water (just like that it disappeared mid-game) and purple textures (mainly in Novigrad but not limited to) but I tried to ignore that as it wasn't affecting the gameplay. But this... I killed Caranthir and I'm able to swim up to the surface. Then the cut-scene is triggered. No matter what I do it always crashes the game. I tried skipping it, doesn't work. Tried switching to dx11, the game cannot even load correctly. No RT ever. Tried various options for anti-aliasing and plenty of other options. Only three mods installed (each compatible with next gen - missing cards tracker, travel from anywhere, no weight limit). Tried to find a solution somewhere here and in other places to no avail. It would be much less painful if it was after like 5-10 hours of the game but noooo. It had to be in the last 15 minutes (or so). Thanks CDPR for waisting my time and for my frustration. Right now I wasted 10 times more time on finding a solution than it would take me to finish the main storyline.

Anyone who encountered this problem and was able to fix it?

And yes, the game did crash on occasion but it was a nuisance not a pain in the ass like the problem above.

One of those three mods that are you using may causing this crash issue. First delete all of them and try again.

If problem will be still there then try on DX11 (if it not starting then above is solution for that) or rollback to 4.01 update and try to finish this crashy place quest and after that go back again to 4.02.