Speaking only for myself, I'm not comparing it to random/theoretical OS projects. I'm comparing it to emacs. Sublime is beautiful, but emacs is a lot more likely to survive, and historically, emacs upgrades have broken fewer things. There are also more packages and more available information on how to build things that aren't available. Configuring packages in Sublime wasn't that great.

Obviously, some folks prefer Sublime. But I'd be a lot more interested if it was open source.