I study math at uni and I was shocked realizing all my teachers use ubuntu on both their laptop and work desktop
It’s probably like the US military and their missile silos still using floppy disks. Better to keep a time-tested and very familiar system running a critical operation than a new one with a bunch of unknowns. Or like when you go to the bank, and the screen the teller is looking at is just a front end going through a dozen different layers with COBOL code written by long dead or retired people on a mainframe at the other end.
Us end users with very low risk can afford to continuously live on the bleeding edge.