My comment is discussing the defaults. Most users will use the defaults and not customize their editor, especially if they are just using it for the first time. The defaults are important.
The single threaded issue is a problem, but one that can be somewhat worked around. I consider emac's bad deals an existential issue that significantly hurts adoption.
> Most users will use the defaults and not customize their editor
But those are not the users who choose Emacs in the first place. Emacs is made for customization.
Besides, there are many preconfigured distributions of it, such as the one discussed here, which can effectively be used as the defaults, if you don't like the ones shipped OOB.
> I consider emac's bad deals an existential issue that significantly hurts adoption.
Well, I reckon you're wrong. Emacs in all of its incarnations has been in use for nearly half a century, and its adoption has never been greater. Some people will point to low percentages in developer surveys, but that is the wrong metric to focus on. Its usage will never reach mainstream numbers, which is probably for the best, but it will continue to be enjoyed by enthusiastic users for a long time to come.
The single threaded issue is a problem, but one that can be somewhat worked around. I consider emac's bad deals an existential issue that significantly hurts adoption.