You can claim all you want that "dynamics" can have different meanings, but fact of the matter is, in music production, it doesn't. And I say that without any implication that you need to have more dynamics in a song like this. You don't. The lack of dynamics here isn't a case of over-compression, it's just the genre.
That being said, there's a couple notes I'd give you:
For a genre like this, I think you've actually got 5 songs lumped into 1 here. I'm basically hearing riff salad. I get that you want chaotic, but I still think that you're too all over the place.
To go along with that, I think the song is too long. Split it up, pick out the riffs that actually mesh together, develop multiple songs.
I don't think the guitar tone is clear enough.
For all of the above, if you haven't already, listen to Abandon All Life by Nails. It's along the same lines as what you seem to be aiming for here, and it's done incredibly well.