Edit: Solved/Work Around - I tried dropping the desktop to 144Hz, instead of 165Hz, and the issue has stopped.
I switched from an old 1080p 60Hz monitor to a new 1080p 165Hz monitor. The game also patched to 1.3.3069.
Since then it seems every time I interact with the UI it causes the screen to go black for several seconds. I have seen videos of people with rapid flashes but this is several seconds in length and only occurring when I interact.
Click "New Game" black screen. Click "Load Game" black screen. Click on a bed, black screen. Click on a character, black screen.
I have tried unsubscribing from all mods, though none were active, and completely uninstalling the game (including deleting appdata\LocalLow\Ludeon Studios). I have then reinstalled but still have the same issue.