I think that what you need to bear in mind is that there are no absolutes in terms of what pickup will or won't work for a particular genre - it really depends on what suits you and your playing style. Personally, i would have absolutely no issue in using a low powered PAF style humbucker to build a crushing modern metal tone, but I pick pretty hard, so I don't need a super hot pickup all the time. Not everybody is the same, so, certainly, some players want a more traditionally "metal" recipe in order to get them into that zone.
With the Polymath in particular, it's a medium output pickup with a really broad voicing, so it gives it a lot of appeal to a lot of different players, all the way from those who like a ballsier-than-vintage pickup for low gain playing to those who like a dynamic, controllable pickup for high gain and everyone in between. Certainly, running the pickup closer to the strings delivers a crisper attack, so I know that Nolly really likes how that works out for his playing style.