>How do they solve the problem without requiring, at minimum, closing all of the user's applications and restarting them, then closing all system services and restarting them? (At which point, you've basically done a de-facto OS restart.)
Settle down. You seem to be taking some heat in the comments, so I'll recuse myself from this discussion, as I feel we are no longer making progress in an intellectual context.
It would help to "make progress in an intellectual context" if you'd deign to back-up the claim you made, which I now strongly suspect was simply incorrect from the start.
But this is not what you suggested, is it?