Ah, yeah. I spent the early 2010s writing front-ends in AS3, so imagine how that turned out. I wrote my own event system too when I was forced to head to javascript, but in the end I mostly just used jquery's, and it's still what I use. I agree the event-driven paradigm leads to sloppy code, but static event names are enough of a clue to what's invoked most of the time, even in relatively large projects. And most things can sensibly just be promisified now anyway, besides user interactions.
I thought it was funny that you wrote this way back when:
>> I've often seen projects where I think "what talks to what and how? What is the separation of concerns and where does this code live?"
And that’s not true! He did want to keep the editor stable and available for many platforms and compatible with vi. Rejected proposals break one of these rules.