same deal here, new Mac Studio Ultra, Monterey 12.4, UE5.0.2…based on some of the stuff y’all have said above, I’m using a USB-C to C cable to my monitor, but that lets me plug it into the front of the computer, which means as soon as it freezes up, I can yank the cable, wait a second, and plug it back in pretty easily.
This is the silliest workaround, but it’s better than waiting for a restart cycle. I’m able to pick back up where I left off. So this is definitely an apple thing, or at the very least a handshake/drivers thing. Good luck friends!