I don’t think there’s any chance the outcome of this will be allowing the communities of orphaned games to maintain them.
However, I think a good middle ground would be requiring publishers to state ahead of time (and inform customers clearly before they make a purchase) how long they will support their game. They should then be able to extend this period, but also be required to refund customers if they drop support before the initial support period they announced ends. Also, there should be a mandatory minimal length to the support period (like some countries have a mandatory warranty period for some products).