You could have legislation, just make it so that they have to keep a download button for people that already have something purchased. The real issue is that like if Sony doesn’t have the rights to something anymore then the rights holder can go after Sony. You just need a rule that they can keep something and can’t be suedby others for providing downloads to customers even if Sony lost the rights, so that only applies to new sales.

I know, but it’s what should happen. People hold the power to make it happen but don’t have any restraint to follow through.