It's actually no longer experimental as of the Gitea 1.21.0 release. (It was released in Gitea 1.19.0 as experimental pending some hardening and additional features that they wanted to add, which have now been completed.) It is still under active development, but is a lot more mature now.

Like you, I have been using it since it was experimental, and it has been very nice.

My only complaint with Gitea Actions was that it required Docker specifically, not other OCI-compatible runtimes, but they recently added support for rootless Podman, so even that is no longer a complaint.