It's a bit of a tricky question, to be honest, but yes and no. If you mean if YT-DLP downloads the best quality that PH website offers, let's call that "PH source quality", then yes, it'll automatically download the highest quality available. If you mean "true" source quality, equal to what the content creators/studios have on their computers, then no.
YT-DLP is only able to download the highest quality that is available through the link you give it. And from a quick comparison with torrents, "PH source quality" isn't "true" source quality. Without going into much detail,
XXX-PAYSiTES torrent releases follow some guidelines ("Scene Rules" or "Standards") of which one guideline states that the release can't be reencoded. My best
guess is that PH does re-encode videos, in a way similar to what YouTube does, but I've not been able to verify this.
For some smaller PH-only creator(s), PH will for sure have the best
publicly available quality, but it'll (
very likely) still be reencoded, and thus not be the same quality as the creator has locally, unless the creator shares the file(s) elsewhere.
If you're looking for "true" source quality, you'll need to use a different website that YT-DLP supports that also hosts source quality files (I sadly don't know any off the top of my head, sorry), or you'll need to use torrents (which YT-DLP does not support).
