I always take one of two extremes: either the website has to work without JS so I need to make it so that everything works when JS is disabled, or I'm going to

I always take one of two extremes: either the website has to work without JS so I need to make it so that everything works when JS is disabled, or I'm going to assume JS is enabled and I'll be going all-out. If you're making a website, I'd say you should try to make it work without JavaScript, and in a lot of cases it can be achieved without that much effort. Blogs, news sites, docs, etc. are typically easy. However, if you're making an application, I'd argue that it's pretty much impossible to do it without JS. It's possible if you're willing to implement your application multiple times (once in a JS-heavy way, and once in a JS-free way), but that's not feasible for most people. The other possibility is implementing it in a way that's friendlier to JS-free users, but for any non-trivial application that'll lead to a really shitty experience for most users. You just can't do sophisticated interactions when you're making something JS-free.