There's clearly the intention to self-host, they seem to be waiting for support to ingest data from a GitHub data export which seems pretty reasonable.

Yes, this is exactly the case. Lots of data, and low ratelimits don't mix. All except for the main repo have already migrated to gitea.com

Disclaimer: I'm one of the members of the technical oversight committee of the Gitea project, and am employed to work on Gitea.