[superkuh]

That's an understandable take in nearly all commercial and institutional contexts. But in others just involving human people, no. Many times JS does fail or isn't available. So building progressively enhanced web documents preserves utility across the spectrum of human visitors (and maintains accessibility). But if you only have a profit motive, then yes, there's no need for robust solutions. The amount of people that can't do JS well won't eat into profits or cause enough complaints to get you in trouble.

[lelandfe]

I think progressive enhancement is a cool approach to building stuff.

I also think “turn JS on” is a fairly reasonable ask these days. A lot of the web tends to break when CSS is disabled or fails, too.

[spankalee]

If your HTML or CSS fails to load, you're going to have a hard time too. Web pages have many critical resources.

[superkuh]

Failing to load is not a problem. Failing to execute is.

Usually because the web dev have used some new Javascript feature only $latest JS engines support. HTML and CSS if they're there they're there. Sure, there's caniuse for HTML and CSS. But they only have to load. The text/images/etc will be there. JS both has to be loaded and executed. If the later doesn't happen just right then the text and other multi-media won't be there. It's a very big difference.