Is this cause even worth a movement?
Consider that basically every live-service game you have ever played will become unplayable sooner or later, and how many modern AAA games are live-service...
We can still play the NES version of Mario (1985), but we can't play Evolve (2015), Anthem (2019), Concord (2024), etc.
Yes, absolutely! I personally want to be able to play games many years after they are released and after they have stopped receiving any support. Yet we see growing number of examples where this is not the case and you get locked out of a game permanently when its publisher decides it no longer wants to support it.