Now maybe you're unfamiliar with audio mixing , & you're thinking "okay there's clearly a visual difference, but how does that translate to what I'm hearing?" Basically when there's more definition in the wavelengths, there's greater dynamic range between the instruments. In the case of music, dynamic range gives instruments more "breathing room" so-to-speak. While there are exceptions, in most cases you don't want instruments to compete with each other for dominance. You want them to harmonize together to create new & interesting sounds.
So what's happening is that in the left image from Doom 2016, the instruments have greater dynamic range which is shown from the wavelengths not being as compressed together, giving the instruments that "breathing room" I was talking about. HOWEVER, the image on the right from Doom Eternal is not this case. The wavelengths on each instrument have been compressed to the point where they are all playing back at the same volume, with exception to an occasional peak.
These heavily compressed mixes were then thrown together and had their combined master volume lowered, which is what creates those seemingly perfectly parallel edges throughout. The instruments are all fighting each other, & thus the mix sounds very poor as a result. Mick Gordon is a far more talented audio engineer than me, it's not even close & that's what makes this especially frustrating. I expect much better from him. Again, the music itself is phenomenal, but this mix on the official soundtrack is frankly terrible.