I found Travis can’t find 2.7, 3.0, ruby-head on x64 Ubuntu 22.04 LTS. This is the build. Though 2.7, 3.0 ruby is supported. And they are on S3 judging from the index. For 2.7, RVM tries to find 2.7.1 ignoring 2.7.7. Is there a configuration file to the RVM that needs some love?
For ARM, RVM finds Ubuntu 20.04 LTS packages. It might not be desirable.