There was a time when the command line was the best thing you had. It meant you couldn't just sit down and start doing stuff. You had to learn commands. This applied to applications like text editors also. I'm not here to evangelize for command line stuff, but now, when I have the choice of the command line, or something graphical, I very often choose the command line because it's quicker and easier now that I've paid my dues on the learning curve.
When I entered the Unix world, the most popular editor was vi. (I had a little experience with ed, and I'd come from other operating systems with editors whose names I don't even remember. My brother even wrote his own homebrew text editor for a homebrew computer in one weekend, but it was all command line oriented.)
When I tried emacs at work on some kind of Vax computer, it noticeably slowed the computer down, so I stayed with vi, like everybody else. Eventually though, I got an Atari ST as my home computer, and after trying various things out, to my amazement, the best text editor for the Atari was a 'micro-emacs' that had just the most useful emacs commands and nothing else. Those commands got ingrained enough that my fingers would type them out automatically without my even having to think about them. So, when computers got fast enough that emacs was responsive, I'd sometimes use it when I wanted to do something that I thought was easier with it than with vi. I was a computer programmer and none of the other programmers ever bothered to learn emacs. It was only because of that Atari experience that I had even bothered, and I was grateful for that.
I looked at the emacs manuals and tried out various features. There were some things I liked that micro-emacs didn't have or anything else, like delete-rectangle, so I incorporated that into my repertoire, since I used it often enough for it to become 'automatic' and stay 'automatic', but I didn't see the point of learning things that would be so rare for me that I'd have to keep going back to consult the manual.
So, when I see that there are even more features, I scratch my head. For those that want to learn all that, more power to them. Maybe they're on to something. Maybe one gets to the point where they're just in emacs and do everything with fingers hovering over the keyboard and it's really fast and automatic and one never has to reach for the mouse and that's really cool. But personally, I don't think I'll be having a go at it anytime soon.