[User23]

Where exactly would you propose building them? A competitive university is going to require around 2,000 acres of land. Where are you going to find that in today's California? No doubt there is plenty of open space left, but it's not in very desirable areas.

[watwut]

The university does not need to be whole separated city nor include amusement park and catering.

It can be an institution integrated into a city.

[User23]

Supposing that’s true for the sake of argument: Where?

[actionfromafar]

Take a random hotel and make a uni out of it?

[User23]

That doesn’t sound like it’s going to attract quality faculty.