My best guess would be that the engine just has vast amounts of technical debt. Skyrim (pre-LE at least) had a savegame corruption bug that has been around since Morrowind. And while I’m sure they have rewritten huge parts of the engine over the decades it’s not rare to see bugs persist over generations, and modders complaining loudly about it. The engine has never been great about asset streaming either so no surprise here.
My best guess would be that the engine just has vast amounts of technical debt. Skyrim (pre-LE at least) had a savegame corruption bug that has been around since Morrowind. And while I’m sure they have rewritten huge parts of the engine over the decades it’s not rare to see bugs persist over generations, and modders complaining loudly about it. The engine has never been great about asset streaming either so no surprise here.