They could just actually sell things instead. As in, sell for real, not some at-our-discretion lease. Nobody's forcing companies to gate access and add DRM and all that. Such a change probably wouldn't result in perpetual hosting, but in actually selling things. Or, in only providing rentals. Either way, the situation would be clearer to the end user.
In the case of games, anything that doesn't mean losing access to an account stops you from being able to play games you already bought. So, GOG wouldn't need to change much, but Steam might. Wouldn't have to mean shipping physical media.
Or they can just stop using terms like "buy" and otherwise implying ownership, instead making it clear you're just leasing the game.
