Maybe we should ask Frederic Cambus to weigh in on this given that EchoJS.com/about has conflicting guidelines: one part days JS, HTML5, and other FE-related content, another bullet point days JS content only. My guess would be this forum would shrink in the amount of content that is posted if it were just JS and nothing else, given we already see such a heavy mixture.
I am all for keeping this pure JS. There are other places for CSS / UX / HTML5 / Swift (all stuff that people have posted in the past). The chances are many of us follow CSS specialized sites anyway, then we get the same news more than once.
As for the content shrinking, so be it, it's about quality, not quantity.