Well, I wish I had known before updating that this would cause issues. The graphics are extremely glitchy now, rendering the game essentially unplayable. Does anyone have an idea on any type of fix for this aside from reverting back to Windows 10?
I believe Streamer Kilgore Trout had this issue on GOG's Twitch channel when he was playing Arcanum on Windows 11, he did fix it but I don't know how he did it, I would suggest checking out GOG's twitch page and see if the replay of it is still up and see if he fixed it on Stream or maybe see if you can contact him directly and ask.
He's on the forums so you can always DM him if he has messaging enabled. He probably won't mind helping you get it fixed. If not, message him on Twitch like the poster above me recommended.
Kilgore is a great guy. If anyone knows how to fix it, he does.