Part of the reason tuition costs more is because the Baby Boomers and Generation X decided they didn't want to pay as much in taxes as their parents did, and so public education got less funding--in some places, as much as 90% less funding compared to 30 years ago.
For example, in the 1970s, the state of CA covered more than 90% of the UC system budget. In 2020, CA only covered around 10% of the UC budget.
Sorry, but that is not even close to the truth. The state covered only 32% of the UC system budget in 1974 when 18% of the state budget went to higher education, and it covers 16% of the UC budget now but the state spends 12% of its total budget on higher education. What changed? Proposition 98, which mandated that community colleges get a bigger piece of the allocated higher education funds -- they now receive 58% of the total (22% UC and 20% CSU).
For example, in the 1970s, the state of CA covered more than 90% of the UC system budget. In 2020, CA only covered around 10% of the UC budget.