> What is happening to this paradise state?
In a word, history. If you just look at the last few decades you're seeing only a snapshot of an explosion.
California (the USA state) is young, ~150 years old.
For thousands of years only ~100k-300k people lived here.
> Settled by successive waves of arrivals during at least the last 13,000 years,[40] California was one of the most culturally and linguistically diverse areas in pre-Columbian North America. Various estimates of the native population range from 100,000 to 300,000.
The Spanish only got started in a big way in 1769 or so, then...
> In 1821, the Mexican War of Independence gave Mexico (including California) independence from Spain. For the next 25 years, Alta California remained as a remote, sparsely populated, northwestern administrative district of the newly independent country of Mexico.
Then we Americans got in on the act.
> When Commodore John D. Sloat of the United States Navy sailed into Monterey Bay and began the military occupation of California by the United States, Northern California capitulated in less than a month to the United States forces.[67] After a series of defensive battles in Southern California, the Treaty of Cahuenga was signed by the Californios on January 13, 1847, securing American control in California.
But before anything could really happen gold was discovered.
> In 1848, only one week before the official American annexation of the area, gold was discovered in California, this being an event which was to forever alter both the state's demographics and its finances. Soon afterward, a massive influx of immigration into the area resulted, as prospectors and miners arrived by the thousands. The population burgeoned with United States citizens, Europeans, Chinese and other immigrants during the great California Gold Rush. By the time of California's application for statehood in 1850, the settler population of California had multiplied to 100,000. By 1854, more than 300,000 settlers had come.[70] Between 1847 and 1870, the population of San Francisco increased from 500 to 150,000.[71] California was suddenly no longer a sparsely populated backwater, but seemingly overnight it had grown into a major population center.
During the ~150 years since, California has become "the largest sub-national economy in the world" with a population of nearly 40M people.
> The economy of California, with a gross state product of $3.2 trillion as of 2019, is the largest sub-national economy in the world.[14] If it were a country, it would be the 37th most populous country and the fifth largest economy as of 2020.
All this happened in the blink of an eye, and before there was a lot of what we might call "adult supervision", in the sense that things like water supply were dealt with without deep thought about long-term consequences.
E.g. "land subsidence": We have taken so much water from the ground that the San Joaquin Valley has sunk many meters! Here's the classic photo showing the subsidence:
https://water.usgs.gov/edu/pictures/full-size/land-subsidenc...
So that's what's happening in the paradise state.