My humble suggestion to GGG on how to resolve the situation: let us play what's in the vault forever

1. Face the reality the organization is not capable of continuously improving two live service games
2. Restore Path Of Exile 3.13 Ritual league (I know this is harder than it sounds but stay with me)
3. Add the current Atlas tree
4. Add the currency exchange, Mark said it's not league dependent.
5. Charge a nominal subscription fee for eg $10 per year.
6. Have a skeleton crew run this, in an ideal case even slowly fix a few bugs.
7. Perhaps eventually if you can spare the resources, slowly add more existing leagues on top, for example Crucible and Sentinel would make the experience even more fun.

If you do not think there's a market for this then crowdfund the process. You will see.