I'll float this idea.
Death metal comes from out there beyond us humans (the eternal). We take and fit it regionally whether in Europe or the Americas. Death metal is more of a universal.
Black metal comes from within the Northern European soul. Its best releases were in the midst of the appropriate cultural setting. Black metal is more of a regional art.
North Americans would have been better off perfecting an industrial, Anglosphere grindcore, or other contra-modernism regional particular, from the mind and soul of the thoroughly modernized. That isn't to say that the two, three or four worthwhile American black metal bands should not have happened. It is to say that in retrospect, the emulation trend did not pan out, likely because the black metal art is not a universal fit and because each world region may have its own particular form of underground (thesis opportunity: enumerate these) in addition to the universal death metal one.
My guess is Americans for the most part have thus far missed the boat on their own regional particular. Speed metal had its appropriate time as did thrash.