I don't expect developers to go out of their way to make the site work perfectly for me but I need to see something to convince me that it is worth a chance.
I'm not asking people to go days out of their way to make their websites work perfectly for people who don't use JavaScript, but please use basic best practices for website layout so I can at least have some idea of what your website is about.
But you are. If you've made the design decision to support progressive enhancement, testing a fallback for each individual element being enhanced is a minimum marginal cost. If you've made the decision to simply require JavaScript, many tasks get substantially easier and you eliminate a large fixed cost as well as the small variable cost.
But let's say, for sake of argument, that any site could magically be made to work JavaScript-free by the wave of a wand and 15 minutes passage of time.
You're still too small of a minority to justify 15 minutes for most people. Several years ago, Yahoo generously identified you as approximately 1% of global visitors across all user agents. Now consider that most visitors come from a refer with some context, so you already have some idea about what content you'll be seeing. If you don't care enough to enable JavaScript, your probably unlikely convert. If 2/3 of you turn JavaScript on (also generous) and typical conversion rates are 20% (very generous), you're looking at about 0.1% of total visitors.
Furthermore, as you prove, the category of people who disable JavaScript deeply overlaps with the category of people who haphazardly call other people's hard work "shoddy". These people make annoying customers.
You're simply not worth it.
Also 15 minutes to convert 0.1% could (and most likely will) still be worth it. There is no magical number for this. A myriad of factors come into play. You can't just issue a blanket statement that I am not worth it when you have no idea what I am worth or the worth greatly changes from site to site.
Requiring JavaScript for your website is not a deal breaker for me. Requiring JavaScript to see a single pixel of the website is what I am complaining about.
Hypothetical: CDN X is having problems, and your scripts don't load. Errors pop up everywhere. Do you:
a) realize that scripting can and will fail for anyone, and tailor a page to work without it;
or
b) continue to plug your ears and point to statistics?
I have scripting enabled, but block Google Analytics and various advertising hosts. Do I count as someone to be supported? Or am I irrelevant because I'm a minute statistic?
I'd ask you if you always wear several blinking reflectors, but I fear that this analogy breaks down very quickly.