Earlier quoted context omitted.
With all due respect, ruby is a language, and rvm is a collection of really fragile and dangerous shell script hacks.
RVM provides a great service to people who work on multiple projects with multiple dependencies across the range of Rubies. Knowing how complicated that type of development was before RVM, I can attest that it may many people's lives a hell of a lot easier. And if you bother to RTFM, is very easy to understand and employ every day, compared to other parts of the Ruby ecosystem who don't have a talented developer supp…
Managing multiple versions of Ruby and all the gems is very easy manually.
RVM is a buggy collection of extremely fragile and dangerous scripts.