Quite a few EU national libraries have legal desposits of cultural works extended to video games. It's not that far fetched for them to expect that their copies should be working. For ephemeral GaaS the libraries could require a video of a reference playthrough for any new game mode, if they don't want to leave it all inconsistent and spotty twitch and letplay youtube coverage.

Requiring GaaS Server binaries to made public is a bridge too far here to me, if the game is kept running with a minimum of two years after announcing EOL and shutting down purchases in shops after that. It should be encouraged, but mandatory? Playability is not everything if the experience is not reproducable to begin with.