"Taxing the wealthy", aka prop 30, was estimated to bring in $6 billion a year for CA.
For perspective, their 2016 budget is $125 billion.
The economy is inflated right now, when it deflated in 2008
California lost over $15 billion in revenue. It stands to reason that they gained all that back, and more, during the rebound and easy money policies from Wall Street. In fact, to demonstrate how much more additional revenue the market has given California, their 2016 budget is 42% larger than 5 years ago. Sounds like they've gained $35 billion annually. Far more than the tax provided.
I have no doubt the tax helps balance the budget... but based on the numbers we're working with the OP's attribution is more than generous, it's flat out wrong.