Well, in our case, we did research.
D18 will graduate early, with two minors, saving us a bunch of tuition. And not a single worry about housing, registration, advising, crime, jobs, etc.
The housing stock is mostly newer and upscale, with AC, gyms and your own bedroom and bathroom. Like staying at the Marriott. And cheap compared to CA, as well, as food, utilities, transportation, etc. Not every fine university is located in NYC, Chicago, Boston, DC, etc.
The extra OOS money, for zero hassles was worth it for me. And you get B1G sports, not the dreadful Pac 12. A “critical” element for D18.
As I mentioned above, D21 just started Cal Poly SLO, so no worries for two years. After that, then it’s time to worry. But at least it’s about $10,000-$15,000 cheaper than the UC’s.