> this requires nonfree Javascript

So... I get the motivation for including this, and I understand Emacs's roots. But IMO this mindset — the one that motivated including this disclaimer - is also why efforts to "modernize" will pay an extra tax, possibly preventing its success.

Emacs has a prioritization rubric that places freedom above mainstream utility. That's perfectly fine, but it inherently limits 1) its audience size, and subsequently 2) its contributor pool and 3) financial upside - either direct or indirect (used to support the project).

This means it will always lag behind the projects that are setting the bar for what "modern" means.