The region thing (along with vim modes) is probably one of the biggest pieces of pushback I've gotten from the piece, and I think it certainly has some merit to it. If you can use movement commands to define a region, and then act on that region, isn't that the same as vim's composability in effect?

I think the best answer is "sorta, but not really."

The biggest reason why is that Emacs commands don't all work on a region by default. Yes, there's C-w to kill-region, but there's still C-k to kill-line and other special-purpose commands out there. In Vim, there aren't four special-purpose delete commands and then a general-purpose one, they all work the same way. This feels like a qualitative difference to me -- both in theory, and in practice.

When I used Emacs for many years, I definitely did use the region commands, but only when the special purpose ones wouldn't work reasonably (like deleting large chunks of code). If I just wanted to delete (for instance) the stuff inside an HTML tag, I wouldn't try to mark off a region and then delete it, I'd just delete by word/character until it was gone. In Vim, I'd "dt>" automatically, because that just makes a lot more sense than repeatedly typing "dw".

And ironically, Emacs has a command (M-z is the mapping for kill-to-character) that would do exactly the same as that Vim command. But in fourteen years of Emacsing, I never even looked for it, because Emacs doesn't steer you that way. Vim makes you always think about what object you're applying your command to, and because you always have to make a choice, you look for good choices; Emacs generally defaults you to one of a few often-decent choices, and you don't get into general-purpose mode unless the built-ins are unworkable.