Sadly, that would actually point the other direction. Ruby was red-hot circa 2010, and while it’s still widely used, it’s not the new shiny thing anymore. I would expect to see more “legacy maintenance” Ruby work than brand-new ruby work these days.

I only have anecdata but all that I have of it points to agencies being heavy Ruby/Rails users and React as well.

Both of them work well since they impose a structure and programming model that basically works for a lot of business software, so you can focus on the domain problems and move quickly over the standard tasks like an asset pipeline or account management.

Ruby is definitely not new and shiny. There are plenty of long-lived Ruby on Rails projects that need to be maintained.

Makes sense not seeing React, though. It is far more complicated and fragile to get SEO-friendly pages rendered with React (and there aren't many legacy systems that use it, either).