I've found that loading in at 4k and then setting your console to 1080p while the game is minimized has solved my crashing thus far tonight. I literally could not enter Orsinium before I made this change. And I'm not talking about the enhanced 1080p mode in the game, I'm talking about the global setting on the console itself.
Btw, my graphics stayed at 4k after setting the screen to 1080p while the game was minimized.