I evaluated it again a couple of weeks ago and there are basically no differences right now (besides a few cosmetic ones) because the hard fork happened just a few months ago. Stick on 1.22 for the time being, it's the last version from which Forgejo supports in-place upgrades. You'll have to transfer data half-manually or perform deep surgery on the database if you upgrade past 1.22 and then decide to switch forges.

Although the next version of gitea should include support for full mirroring from GitHub (so periodic synchronization of new issues, PRs, etc), not just (code mirroring XOR one-off full copy) like it does right now. This might be of interest to you.

A lot of their early value-proposition were saner security defaults and additions to increase confidence in the software's security. A lot of the changes were attempted to upstream into Gitea, but not everything made its way in. They were a soft-fork for a while before hard-forking, and even after the hard-fork continued to sync changes from Gitea where possible.

Forgejo v10 is the first release I've seen where there's been a focus on tiny UX improvements (versus trying to remain compatible with Gitea). I'm hopeful these will continue to come, but it does still feel essentially identical in appearance and functionality with Gitea.

They have a FAQ (https://forgejo.org/compare-to-gitea/) TLDR: Forgejo is free software, prioritizes security and stability over new features and is actively developing the federation module (thus working to enable communities of federated forges)