If they don't have a basic backup strategy that keeps a copy of at the very least current client code, current server code and a reasonably up-to-date server data snapshot somewhere safe but readily accessible if needed, then there are way bigger problems than "will we get an offline mode someday" such as "will the company survive at all when it's its turn to be hit by ransomware?". That's not a "oh, that was Bob's project and he left five years ago" optional extra.'Plan to'. Would be nice if they confirm or deny whether such archiving is actually happening. I doubt it, since quite a number of core developers had rotated elsewhere by now.
Whether they're also keeping backups of much older code and data so that you could also run the original 2.1 with the galaxy of the time as well, maybe not.
But it really shouldn't be "we don't actually have an archive of code and data" that's their excuse in N years time for not providing it.