Funny I upgraded to ubuntu 20 from 18 last night. Ruby sass wouldn't work anymore. Why? Well just read what the maintainer said...

"When Natalie and Hampton first created Sass in 2006, Ruby was the language at the cutting edge of web development, the basis of their already-successful Haml templating language, and the language they used most in their day-to-day work."

The page continues...

"Since then, Node.js has become ubiquitous for frontend tooling while Ruby has faded into the background."

https://sass-lang.com/ruby-sass

So I installed the nodejs version. And in a few years I'll move over to the next fad....