FWIW keyboards have worked OK all along, I regularly use one of my wireless keyboards switched over to the phone to type longer stuff, though the autocorrect gets more annoying in that case.

Mice are a lot more annoying, because they're part of the assistive devices, so you need to enable Assistive Touch, and then you either have the mouse connected or the Assistive Touch menu taking space on the display, which is probably not useful if you're abled. If Assistive Touch is disabled, the mouse "works" but you don't get a visible pointer which is completely stupid.

Possibly connecting to an external display won't have that issue, or iOS 17 will make the experience a bit better for non-assistive mousing.