David Kimura PRO said over 1 year ago on A Rubyist's Apple M1 Review :
  not really. A lot of things do compile and work under the arm64 binary of homebrew. As you noted, things like postgresql seem to work. I haven't done any tests with using the system ruby version. However, I have tested things out with asdf ruby and rvm ruby (both arm64 and intel)

Until things stabalize, I'd recommend doing homebrew under Rosetta.