They _are_ in the CI market. Two of their products are the Docker Build Cloud and Testcontainers Cloud. IIRC Docker Hub also came with automated builds at some point (not sure if it still does).

I do get your sentiment tough. For the position they are in, a CircleCI-like product would seem to be quite fitting.

Wow you're right they are. Yeah, they could really use some improvement there.

https://docs.docker.com/build-cloud/ci/

This could've been a "change runs-on to be this" like all the other faster GHA startup products, but instead the way they set it up I would have to keep paying for GHA while also paying for their build cloud. No fun!