When I started learning 2013 and working on Ruby 2018, I used RVM on my workstation. On commercial projects, rbenv was very popular when setting up deployment (with Capistrano); to some extent, it was the unspoken standard on the server.
I like RVM because after installing it, it just works. One of the popular errors was when installing old versions of Ruby and incompatibility with OpenSSL and it works in RVM out of the box.
Nowadays, installing and running older versions is mostly done using Docker (as a bonus, you get an isolated environment).
I’m completely satisfied with RVM, but I’d like to have a more modern tool for working with Ruby versions. I think it will be an RV in the near future. I highly recommend you to at least install it and try it out.
What tool do you use to switch Ruby versions?