Black Metal was never about "radical individualism". It was always about Collectivism, from the perspective of the Individual - "What can I, as I am now, do to improve my family/tribe/clan/other significant group?", as well as "Can I, by improving myself, improve my <group>?".
I believe you are imposing your personal philosophy -- or at least your personal definition of what the philosophy of black metal should
be -- upon a movement that as, a whole, is pretty ideologically inconsistent. An earlier thread
featured Mannheim, admittedly a fairly minor player in the scene, claiming black metal is about individual freedom, while fellow bandmate Euronymous on multiple occasions expressed hedonistic desires destructive to both the self and society. Are we to take these viewpoints completely at face-value? Of course not, the same way we don't take every but of Varg's ideology seriously.
And then there are bands and albums that really show no ideological bent except a juvenile opposition to Christianity. Is Havohej espousing some collectivist ideology? Bathory's early albums, by Quorthon's own admission, were largely schlocky, adolescent Satanism based off pulp lit, and even his later, pagan-influenced stuff was chosen mostly to piss off Christians. Black metal is neither ideologically homogenous nor particularly profound on the whole, yet it remains great, intelligent music. We should not have to impose superfluous ideologies on something to enjoy it.
That said, liberal black metal doesn't make much sense to me. Leftist policies have always been about empowering the weak, while black metal has always seemed to revel in power and its application. So in this sense I think you are right when you say this stuff doesn't fit quite right, but you are wrong on what this inconsistency is.