you said it yourself.
"added such an insane feature list in the last few years "
those people are there more then few years. so this improvement has nothing to do with these people ( except managerial role ).
Huh?!
Emacs maintainers do an insane amount of work! They know most of the code, write new code, review code submissions, support a bunch of mailing lists and answer numerous stupid questions.
It would be nice to get a better GC in, and the long lines. It just seems like the author is acting as though they are the only ones to be attempting to make real improvements despite the obvious efforts by a good few other people.