"Insane" how? Its budget is $5,430 per person, 33rd in the nation. The highest is North Dakota at nearly $20k per person. California falls between Nebraska ($5,024) and South Dakota ($5,575)[1].

It's big because it's a big state. If it were a country, it would be in the top 50 in the world by population, and 5th by GDP. It's got issues of its own, like any other large organization, but there's nothing particularly out of line about its budget.

They're doing this not because the budget is in deficit (it was going to be in surplus this year, before the pandemic, and had been in surplus for a while) but because it wants to shift the burden of its budget to those with wealth (and away from the middle class, especially the lower-middle-class). It may or may not be a good way to do that, but it's not because it's desperate for money. Quite the reverse: it's got so much money that it gets to choose how it funds itself.

[1] https://en.wikipedia.org/wiki/List_of_U.S._state_budgets