Which is almost all states, except for a few that had increases in such things as oil and gas money (e.g. ND, WY). Voter demands like lower taxes and more prisons (due to increased sentencing / “three strikes” laws in reaction to the crime wave that peaked in 1991) means that something had to be defunded to balance the state government budget.
Generational priorities may also have something to do with it – the large baby boom generation is mostly past the age where they have kids in high school and college. That the baby boom was predominantly white while the current generation of high school students is just barely majority white adds a racial/ethnic angle to the generational conflict.
Of course, the result of defunding the state universities is that the state universities can only afford to enroll so many subsidized in-state students, or reduce the subsidy (in-state tuition discount and/or in-state financial aid) for each of them. If they have empty seats, they go looking for out-of-state students who do not get subsidies, or pay more than the cost of educating them (a contrast to the past, when some state universities charged out-of-state students less than the cost of educating them in order to attract them to the state for school and then potentially stay and contribute to the state economy afterward).