For most of the period from 2020 to 2023, /pol/ has had more posts/day than any other board, often substantially more and it was 2nd most of the time. The /vt/ is a pretty distant 4th behind /v/.
I'm not entirely certain that I would call /pol/, which generates upwards of 110K posts/day a tiny phenomenon. It's about 13% of all 4chan posts. Add in /b/ and it's about a fifth.
And of course, casual bigotry is all over 4chan, not just /pol/.