About one in thirty (ish) - relatively rare, but still too many [1].
I can speak with some confidence as I browse almost exclusively without
js. If a site needs it, I just move on [2].
Most sites still render a lot (sometimes revealing more) of their
content perfectly without it.
As other HN commentators have noted, there's a strong negative
correlation between sites that are js heavy and quality. Very
little of value is lost by avoiding them.
[1] Too many because it seems a those that don't work without js also
break legally required accessibility standards and are mainly from
bigger entities who should behave better.
[2] About the only thing I can't seem to do on HN as a text-only
reader is up/down vote other posters. That's also a feature.
