Ask HN: Lightest Linux distribution (DE agnostic)

Okay, now I realise that this question has been asked​ and answered way too many times to be asked here, but I noticed that at every single place possible, the distributions are compared keeping the distribution in mind. When they say Ubuntu, they mean Unity, Debian means gnome and so on. But consider if all distros used the same DE (say XFCE)? In my opinion, this would help us choose better.

Thanks in advance