Math world can definitely be snotty. FWIW math phds earned from 2013-17 by those who went to TTech undergrad were 11 (3,2,3,2,1), Vandy 7 (1,2,0,3,1)
You can see how those numbers stack up in this handy, searchable tableau database for undergrad institution of those granted phds from 2013-2017
https://highereddatastories.blogspot.com/2019/02/doctoral-recipients-2013-2017.html You can cut it by carnegie classification, state, subject, etc.
If the link isn’t allowed, google highered data stories doctoral recipients.