rbenv seems to work after uninstalling rvm. Yikes, what a horror show. The intelliJ integration isn't perfect, but it'll do.
I tried installing chruby, but after downloading a couple of different python interpreters, a clojure environment, and an erlang environment, it blew up.
What are these guys putting in these systems? Yikes.
I damned near paid $100 to get the Ruby on Mac tool. I mean this is such a horrific process that people are making money off it.

Source: x.com/unclebobmartin/status/1827697094376796439