Seriously. Next time I see an employer “require” notification before I leave, I will simply let them know I require the same. This logic that I can be terminated at will (leaving my family in a poor position) but that I can’t fire them (leaving them in a poor position) is so moronic that I don’t understand how any person can present with a straight face. It’s even worse when it’s presented to you by an employee of a large company who are themselves in a terrible position by having agreed to that policy.
Ask about it up front.