> It is dismissive because if it was just that then knowing the mathematics would be sufficient to do research in theoretical quantumn mechanics but it isn't.
This not at all the same. QM is a special case of QFT.
> To say that theoretical quantumn mechanics is just a small branch of mathematics is ignorance.
It’s not. That statement is objectively true.
> It is not insightful at all.
It is.
https://en.m.wikipedia.org/wiki/The_Unreasonable_Effectivene...
> Is commutative algebra just a branch of set of theory? Are set theorists generally equipped to understand research papers on Galois Cohomology? No. Set theory is used in these areas but to suggest that these areas "are just aspects of set theory" is not all insightful.
Intersection (overlap) is not the same as containment, so I have no idea why you’re bringing this up.