True, the mods must be considered too. They're usually updated except the old ones that aren't maintained anymore.It broke all the mods so I may have to restart ... but I just ordered a new PC today, with a 4090, so I may wait till I get the new PC setup and running to start a new play through.
I suppose the main feature that may break a saved game is whatever custom item was in the inventory, or perhaps spawned custom items that were visible in the world when the game was saved. That may be tricky to remove. The other mods could simply be uninstalled. But if you'd like to see the new graphic improvements, that may be the perfect excuse to play it again.