It's interesting because some of these bands are older than these terms. Alcest wasn't considered blackgaze until albums inspired by their own sound became popular, for example.

Metal also has history where a genre is aesthetically defined as well as sonically, which complicates things.

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loganc2342 4 hours ago | parent [-]

Black Sabbath, the consensus originators of metal as a whole, weren’t considered metal until albums inspired by their sound became popular, either.

	▲	toolslive 4 hours ago \| parent [-]
		They (Black Sabbath) were booked as a blues band by Jazz Bilzen in 1970. People just didn't know where to bucket sort them at the time.