You are conflating a lot of things there.
First, a BEAD arrangement on a P is just fine or Stoner or Doom, because they don't play fast, they use a lot of distortion, and fuzz pedals like split single coils. They are also into retro looking basses.
That isn't what I'm talking about.
There are A LOT of different flavors of metal. And there are many that you will never see a plain old P bass on. They are too slow, and aren't easily available in 5 or 6 string versions. Nor are 35"+ scale length available. Plus, they look old and dated. Most thrash, death, metalcore, deathcore, groove, tech death, and prog death are done on something with a bridge pickup, and more often than not, are double humbuckers because of their mid presence.