I faced a strange issue a few days back. My bootcamp windows installation stopped working and rebooted with autorepair but with no keyboard input working. I tried internal macbook pro keyboard and external usb kyboard, nothing, looks like usb ports are not accessible for the windows system at all.
I've tried to create a new windows install usb stick through bootcamp assistant and repair the system from the usb stick. But when I booted with the installer, there was no keyboard access as well.
I have an assumption that apple has made some firmware update and it caused problems with devices drivers.
I found a similar topic on reddit but no posts in apple community though. So I created a new one and it was deleted because I'm using beta. But before it was deleted, there were about 3 posts from other users already, who reported similar issues with Catalina. So I have an assumption, that this is not only the beta related issue.
I have:
MacBook Pro (Retina, 15-inch, Late 2013)
With macOS Big Sur 11.0.1 Beta (20B5012d) installed