Earlier quoted context omitted.
This is some long horizon impact. Really just wildly unfortunate to see a disruption that feels unique. It's not due to war, even if academics could 'flee' to another institution, its a discarding of the prioritization of knowledge generation. The thing humanity has been built on.
This seems like a broad overgeneralization unless you believe zero fat in grad schools is available for trimming.
They don't attend classes after ~2 years, mostly operate independently besides consulting with their advisor, don't take anywhere near a professor's salary, teach or TA classes, act as lab technicians, and bring in money through grants.
The costs are mostly upfront in the form of providing the necessary research facilities to attract research-oriented faculty and students, and the administrative staff needed to ensure compliance with grant terms.