Ive never played obliviok but i do know they surprisingly did update fallout 3 to work on modern windows, but they sure took their time considering fixing it yourself meant downloading one file and putting it in the game folders. They really should have fixed more than that though because its extremely unstable and its not great even with mods that aim to fix it.
New Vegas has worked much better in my experience although others have told me they ran into even more issues than with 3, so I’m not sure.