Yamaha FM is best when jagged and rusty, yes. That physical GRAWNK you can get.
Oh yeah, I can hear that empty, dead “TWERNG” tone of so many late-era Genesis soundtracks.This is neatly atmospheric, though. It works kinda like a film score, which… makes sense. When the guitar synth comes in, it reminds me a little of demoscene pitch-bending.
All of which is to say, GRAWNK > TWERNG.