If those users are bothered about a private entity destroying its own (user generated) data then maybe they need to remember they’re on the internet. Big companies haven’t completely destroyed the open nature of the web. They could rent some server space, set up their own phpbb forum and have their own community away from the corps.

Way back in 2006 I returned from holiday to find my beloved gaming forum, ran by a big publisher was closing down. So the community banded together, someone forked out for the setup and we started our own forum. 18 years later it’s still here, with an archive of all the posts from that era.

Build it and they will come.