i believe homebrew is transitioning to golang. all of the tools you’ve mentioned above that are seeing less usage, unfortunately :(
Homebrew's repo is still almost all Ruby with no signs of Go anywhere. A bit of Swift...
And fair enough, tools come and go. Ruby is still the best write-once language I've used though, and Rails is still a top web framework.
Stripe (and Shopify) too?
Check how many top YC companies use Ruby.
The question was how many use Ruby, but not Rails.
You forgot Discourse and GitLab.
Homebrew and YAST (Suse Linux) are written in Ruby. Stripe uses Ruby but not Rails.
Basically anything you'd use Perl for, + a bunch more uses, and of course Rails and web stuff.