Ask HN: Are social sites really dead?

Hey folks, I've been wondering about this. I'm building a cool community over at www.learnsearch.xyz, but people continuously tell me that having any faith in a website built on human curation is a fools errand. I think there's value, and so do my 30 users so far, but honestly, is it really futile to build social web apps today? Everyone seems to be focused on mobile or ar/vr, but to me it still seems that the most stable platform for learning would be on the web.