Many users who need a significant degree of privacy will also be excluded, as JavaScript is a major fingerprinting vector. Users of the Tor Browser are encouraged to stick to the “Safest” security level. That security level disables dangerous features such as:
- Just-in-time compilation
- JavaScript
- SVG
- MathML
- Graphite font rendering
- automatic media playback
Even if it were purely a choice in user hands, I’d still feel inclined to respect it. Of course, accommodating needs should come before accommodation of wants; that doesn’t mean we should ignore the latter.
Personally, I’d rather treat any features that disadvantage a marginalized group as a last-resort. I prefer selectively using <details> as it was intended—as a disclosure widget—and would rather come up with other creative alternatives to accordion patterns. Only when there’s no other option would I try a progressively-enhanced JS-enabled option. I’m actually a little ambivalent about <details> since I try to support alternative browser engines (beyond Blink, Gecko, and WebKit). Out of all the independent engines I’ve tried, the only one that supports <details> seems to be Servo.
JavaScript, CSS, and—where sensible—images are optional enhancements to pages. For “apps”, progressive enhancement still applies: something informative (e.g. a skeleton with an error message explaining why JS is required) should be shown and overridden with JS.