I believe only LGA-1156 was supposed to be the traditional desktop - dual channel, like for ages. HEDT started with 3 channel boards at same 4C (= same core count as desktop), then grew over time.

I don't think they've revealed *THE* problem with their 10nm process, but it seems to essentially be that they are having so many defects on it that they can't make reasonably large chips or chips ...