With static typing and analysis in the editor there’s no reason to run the code for every second line you write.
I usually only need to run it a few times towards the end of writing a feature to see if the compiler or specs catches any errors.
If you're building web apps chances are you want to see your changes frequently since modifying a model, controller action or view may yield a different UI state.
I'm constantly editing code then directing my attention to my browser to see the results. This is independent of CSS or JS changes that might be picked up by asset watching tools like esbuild or tailwind's CLI tool.
Technologies like Docker have made distribution a lot easier. I haven't used tools like chruby or rbenv since 2014 when I started using Docker because Docker manages your app's runtime environment. You pull down your built image on your server and run it. There's no complication, sprawling of version managers or surprises.
Personally I think having a fast dev feedback loop is critically important. It's something you experience hundreds of times a day as you're developing your project.