While it's jarring to see someone call DHH a "white supremacist", the shoe fits. In that blog post he laments that London is "no longer full of native Brits" (what does that even mean? It's clear by the numbers he gives that he's counting "white people born in Britain") and frames demographic change as a "nightmare". That isn't neutral nostalgia (something he's claimed he doesn't have: https://world.hey.com/dhh/legacy-without-nostalgia-b19708c9) it's the same ethno-nationalist logic as "America for Americans", that old KKK slogan. When you argue that a city (especially one that's always been a multi-cultural hub) becoming less white is inherently a loss, you're not just being contrarian. You're espousing a white-supremacist worldview.