If you're happy with `screen` then there's little point changing. The tech industry can often have an air of elitism with regards to tools we're told we "should" use. While sometimes there will be reasonable arguments for or against specific tools, usually the overriding deciding factor is just personal preference.

That all said, I do completely relate to your "[screen] happens to be installed on most hosts" point. That's also the main reason I've never switched to zsh over bash and why I don't run fancy vim plugins.

I had a co-worker about 5 years ago who could do everything I did in tmux with screen. There really is no need to switch as long as your workflow is working for you.