We have something like this already on mobile phones. NFC chips and the radio are pretty much independent systems and the host system has to use message passing

We have something like this already on mobile phones. NFC chips and the radio are pretty much independent systems and the host system has to use message passing to talk to them. The OS as a micro kernel doesn't really yield benefits in this case. Graphics cards and other accelerators are trickier since they can also access main memory. Therefore, restarting its driver might not resolve the problem, and the whole system has to be rebooted anyways. Anyways, the system might not be that usable anymore if a critical driver keeps crashing and restarting...