You’re right; the white supremacist concept of “civilization” would not survive, with its destructive concepts of “primitives” and “medieval tech level”.

That said, people will still have access to scientific knowledge, procedural knowledge, engineering knowledge, cultural knowledge, regional knowledge, etc. Their ways of living may not clock as “civilized” to the sort of people that built Phoenix, Arizona - a monument to white supremacists’ arrogance - but they could live long and happy lives using technology to live within their means.

That said, if Antarctica melts it would have tons of quite easily accessible fossil fuels. So if “civilization” wants to have another go at destroying the world, it could.