I think you covered it pretty well. Blackgaze and OSDM revival seem like the defining tastes right now. There's been an upswing in free jazz influence as well, I think, and I feel like dissonance is experiencing a surge in both.
Osdm is a very saturated genre at the moment and spectacular quality isnt always needed to become popular. 20 buck spin maybe is the best example as they have a cult following them.
Maybe blackgaze, post-black, hipster and stuff like that which was very popular then has lost either quality or interest or both. Raw black metal has become more popular, thats more of a trend than an increase in quality (imo).
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