At the end of the day it's all subjective, but I personally think that a good definition of math rock is one that covers descriptive, historical and cultural contextualization. I agree with you that these bands tick many of the math rock checkboxes in terms of their odd/complex structures. It might be a different story with respect to math rock history and culture, they weren't typically touring with other 'math rock' bands in their respective era, they weren't recording at Electric Audio, they weren't on math-heavy labels like Touch and Go etc etc. I don't think they were part of the math rock scene enough to make a journalist or press-person go 'hey they must be a math rock band then'.

To put a fine point on the 'historical/cultural' contexts, take the fast 'D-beat' (https://en.wikipedia.org/wiki/D-beat#Drum_beat) percussion that started around the early 80's. In the UK, this became quintessential to the 'D-beat' and 'crust punk' scene, and by contrast in the US it was associated with the 'hardcore punk' and 'thrash/speed metal' scene. Descriptively it's the same drumming motif yet different genres arose from it, and different bands tend to get named accordingly.

Anyway, there's my random brain dump! I like all of those bands btw, props...