I often wondered why this is, because he seems like a very smart guy with interesting ideas sometimes, so it seemed kind of weird and conflicting.
Then I learned he's trying to hide his beliefs about scientific racism and political views (1) while often writing in the tone of "pained centrist just wanting to understand things scientifically" and it made much more sense as (in the worst case) an old school propaganda technique of FUD in science and rigorous science to make the HBD go down better and (more charitably) as Mr. Siskind just being another bright-but-human person who when writing on things he has actual expertise on can be very well worth reading, but simply shouldn't be trusted on anything aside from this. Rationalwiki has a decent writeup on him (2)
1: https://web.archive.org/web/20210217195335/https://twitter.c...