>Sublime and TextMate offer convenience but only limited extensibility. On the other end of the spectrum, Emacs and Vim offer extreme flexibility, but they aren't very approachable and can only be customized with special-purpose scripting languages.
It doesn't seem like they (and many others) are denying that Emacs and Vim are excellent editors. Why is ease of use such an important issue for text editors? Emacs isn't terribly difficult to use, but if my livelihood and the majority of my time is tied to what tools I use, then it's worth the investment of time. I don't think I've met an Emacs user who has put in the effort of learning Elisp and customizing Emacs to their liking ever deny the benefits of learning it in the first place. Yes, it's a pain in the ass initially. I quit Emacs twice before I became determined to stop whining and spend quality time learning about tooling.
There is no doubt that Emacs has a steep learning curve and perhaps that's because its developers have a higher expectation of its users. I would argue that these expectations are easily matched by the capabilities of a competent programmer.