QResearch WAS a subset of /pol/ back in early 2018.
That's where most of the oldfags present at the time came from and were busy still doing 2 tabs.
It was only as during mid-2018 that the ratio of those that were/are on /pol/ as well started to move towards where it is today.
A today where the majority of QR DOESN'T also do /pol/.
I'd argue that PTG was the OG QResearch as most of the attendees of that (now long) running thread were the ones that followed Q over to 8ch.