Hard to say, depends on the "track/or song" that you're trying to create, for me personally when it comes to PE/Noise it can be long drawn out to fade when the track seems more "compositional" or when it's more bursted out and spontaneous, could just end in screaming and stop all at once. You'll be the decider in that outcome ultimately. I remember awhile back talking with Patrick O'Neil in regards to something similar on the matter and it seems like with some of the harsh noise and the more compositional type of stuff, like he does in more modern Skincrime that it is drawn out in length with an intent to fit a proper compositional outcome. I've tried to incorporate that idea with some of my works in PE/Noise, but obviously Patrick a lot more experienced and has a much greater "Aube" like focus for such detail can master that sort of achievement. It's a kind of like funeral doom. That entire genre is all about timing and pacing to achieve the great end results often times. I've tried to introduce that sort of pacing with my dungeon synth/dark ambient music too, but it can be a challenge, but ultimately it comes down to what you "the artist" has in mind for a goal and what you'd like to achieve in the grand scheme of things, so really there is no wrong or right way to end a track.