The emacs bias is even part of Lisp advocates mental models, so it's no surprise that a lot of would-be Lispers give up at the thought of having to use it. But there are alternatives, and it might be fruitful for advocates to routinely point them out. vim (my preference) has two slime plugins that work really well, Atom has https://atom.io/packages/slima and as you point out there's lots of Emacs-variants. There's also lem and Second-Climacs might one day be good. And of course there's the two proprietary IDEs with LispWorks and Allegro that both provide trial versions to see if you like them before shelling out money.
Apart from editors, more editor-independent tools would be nice. McCLIM's Clouseau is a pretty cool graphical inspector/variable watcher.
IMO what holds it back is lack of a big company using and promoting it along with tooling (which might be in the form of alternate IDEs or good plugins for popular editors like VS Code or IntelliJ). Clojure has shown what's possible without such, most use emacs but there are popular alternatives too, and for a time it was even as popular as Go, but Go has BigCo backing, and we can see how much further that brought it despite its many shortcomings.
You write lisp without auto-inserting the closing paren when you open a paren? I honestly don't think that's a good idea. It's also something that's contributed to lack of lisp adoption -- people trying to write it without sensible editor support.
Yup, as I type ( and { and [ and " and manually close them in every other language and inevitably turn that stuff off if the IDE has it enabled. vim default has enough support -- when I type ) et al., it highlights the matching opening. Typing '%' in command mode jumps to the corresponding open/close bracket. Occasionally if I know I'm done with a function, and have a bunch of closing parens to insert, I'll use slimv's ctrl+x+0 to close them all for me. I'm a fan of rainbow parens which makes things nicer to look at too, but really, this Lisp meme becomes true after not very long: https://www.thejach.com/imgs/lisp_parens.png Or at least one tunes them out, just like one does with the syntactic noise in other languages. Editing them is natural.
Speaking of noise, here's some out of context JS code from the first random file I opened in a really old project:
Yup, all of those () and {}s and commas and semicolons and single quotes were inputted manually. I say to my editors, "just let me type".
For Lisp, "sensible editor support" to me means something like slime support that enables REPL development. Lacking that in editors besides emacs (or not knowing about the support for alternate editors) has probably hurt adoption, sure, but I don't think the presence or absence of other editing tools that most every editor has (like keyword highlighting and other colors, auto-indentation, auto-completion, auto-bracket insert, intelli-sense stuff...) is a factor.
Apart from editors, more editor-independent tools would be nice. McCLIM's Clouseau is a pretty cool graphical inspector/variable watcher.
IMO what holds it back is lack of a big company using and promoting it along with tooling (which might be in the form of alternate IDEs or good plugins for popular editors like VS Code or IntelliJ). Clojure has shown what's possible without such, most use emacs but there are popular alternatives too, and for a time it was even as popular as Go, but Go has BigCo backing, and we can see how much further that brought it despite its many shortcomings.