I'm having exactly the same issue. After upgrading to windows 11 on my Surface Pro 7, whenever I put my device to sleep by closing typecover, both the camera for face recognition does not come on, and the touchscreen is unresponsive. When I put my surface to sleep via software or the power button, the problem does not occur. It however might occur again if the typecover is closed after putting the device to sleep by either of these 2 methods.
This seems to be clearly related to the opening and closing of the typecover. That is all-the-more clear because of the fact that the issue of the unresponsive camera and touchscreen can be resolved by closing and immediately opening the typecover, although this might take a few tries. It would be good to have this issue resolved instead of having people waste their time reinstalling drivers. The fact that the unresponsive touchscreen and the camera/ face recognition issue always occur together indicates a software issue in Windows 11 rather than anything involving the drivers of the camera or touchscreen.