It can be done though: see what Windows has managed to do with graphics drivers. I've experienced a full crash of the graphics driver and windows just restarted

It can be done though: see what Windows has managed to do with graphics drivers. I've experienced a full crash of the graphics driver and windows just restarted it and kept on trucking, the only casualty being the 3D application which presumably triggered the crash. It's not just a matter of sprinkling the microkernel architecture on your system, but something like that is a prerequisite.