There are a lot of cases where turning off JS is impractical, and I don't do it myself.
But, to me, Blogger is a great example of a site that is poisoned by its reliance on JS. Blogger is so bad at showing a page of text that it needs a splash screen.
Only because Google neglected it. When blogger redesign landed it was exactly what was trendy, heavy js, dynamic layouting. It was slow but at least I thought it was worth the wait / the cost / the latency. A tech demo. Not anymore, I want to read something more than be amazed and don't want to shop for a core i5 to do so and now blogger looks dumb. Google could totally fix it but they had other horses to ride. Maybe one day.
Neglected? It takes a special amount of skill and a lot of work to screw it up so badly in the first place. The Web is designed to display text by default, and Blogger fails at that.
Yes, neglected. They put resources for the js revamp. It was cute at the time, not anymore, Google surely knows it but doesn't want to invest anything here (for now). They just pushed a huge redesign of G+, supposed to be their flagship, vastly simpler and faster (to the point of making it even less relevant). Blogger gets the remains if anything ever drops.
But, to me, Blogger is a great example of a site that is poisoned by its reliance on JS. Blogger is so bad at showing a page of text that it needs a splash screen.