From the other comments, I feel more alone in this camp than I thought. I've taken the stance to not even consider a user, browsing sites I develop, with javascript off. It's such an integral part of the web by now, and without it, interactivity doesn't really exist.
Is it really so prevalent to browse without JS (I doubt the casual user would do that, since they're probably not even aware that JS exists)?
The only reason I'd care about displaying content without JS, is specifically for crawlers.
This is what it comes down to for me. I started browsing with Javascript off after both my cores were pegged at 100% for forty-five seconds to load a page with a 500 word movie review. The pages wasn't nearly as interactive without the Javascript, but I didn't care. I didn't want to interact. I just wanted to read the text.
If your site is an actual app that I'm going to interact with, I'll turn on Javascript. That makes sense. However, if it's something that I'm just going to read, then Javascript stays off.
I browse with JavaScript turned off by default, and have ever since I saw a pretty cool DEFCON (I think) presentation on the number of gaping holes it makes possible. I'll sometimes enable it for a site, but I'll also sometimes just not use a site.
I really don't like the fact that this is getting more and more difficult to do. The Web is not about allowing random people to execute code on my computer; it's about reading documents and sharing information.
Its not prevalent at all. The HN echo chamber makes it seem like there are many people who do this, but the number of people in the real world is basically zero.
The problem with JS is not interactivity but a lot of aggressively annoying advertisement and data grabbing which usually comes along JS.
My solution is to use different browsers. My default browser has JS turned off. If I encounter a possibly interesting site which requires JS then I use another browser for that. This solution keeps my default browser clean without need to configure any JS blocker.
disclaimer: not a web dev, don't really have a dog in this race.
The reaction here strikes me quite a bit - talk about supporting an old web browser which has a small market share, and the reaction will often be that it's a waste of time. No-js users are a miniscule fraction of a typical site's audience, so why would those sites bother to support them any more than they would bother to support an old browser?
I believe there's a difference between not supporting an old, non-standard-compliant browser, where you must have the same functionalities but the platform is different, and not supporting users who have turned off javascript, because in this case the functionalities themselves are different. You almost have 2 different "products" in this case.
Also, angry users are always the most vocal. The huge majority that doesn't bother (or doesn't even know how to) turning off javascript will not complain on HN.
I guess - from my point of view it would be lumped under the wider group heading of 'how much should I worry about going to significant effort supporting stuff that few of my customers will care about?'
Is it really so prevalent to browse without JS (I doubt the casual user would do that, since they're probably not even aware that JS exists)?
The only reason I'd care about displaying content without JS, is specifically for crawlers.