Yeah it's a very real form of lock-in, nothing else really compares to Emacs + Paredit + Cider for productivity. And Emacs isn't great. But when I did Clojure full time for 5 years, I just sucked it up and learned Emacs and got really good at using it. Customizing my init file little bits at a time probably added up to a month's worth of lost productivity. But out of 50 months, 1 month lost to environment setup isn't bad. That's like 2% of the whole time. Or about 48 minutes per week. And the learning curve for me (as a long-time vim user) wasn't as hard as I thought it'd be, especially since knowing bash shortcuts really helped prepare me for the Emacs way. In fact I even took some Emacs knowledge back to the shell, such as how Ctrl-underscore is "undo the last edit to the current command".