That's not an accurate summary of the main arguments. For one thing, on the pro-hg side you've quoted only the opinion of someone (Jordi Gutiérrez Hermoso) who isn't even an emacs dev: the email starts with a note to please cc him on replies because he isn't subscribed to the list! This isn't the view of the GNU project, the opinion of the Emacs developers on why they prefer hg over git, or even the personal view of RMS. You'll get a better summary if you read the thread.
I don't know why people quote ESR like that's still a thing either. He wrote some essays in the 90s, wrote some possibly important code before that time, but one must understand his position on this list is basically troll.
