Time to update this answer.
There is an emacs version called Spacemacs with a vim editing mode.
It’s a distribution aimed at those of us who love vi and its keybindings and the power of emacs as an “operating system”.
So #1: it is possible to like both. I see absolutely no reason why not.
And, based off of that, I don’t understand what you mean by “almost invariably”.
So #2: yes. You can master both. There is no evil demon that formats your HD if you try it.
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