Yup. I don't live anywhere near there, but I've heard that repeated in various "fake news" stuff for a while.
According to a few places online that show population growth since 2010, all California counties over 100k in population, except Kings County, have experienced growth, many by double digit percentage points.
Not to go too far off topic, but if you want to see a mass exodus, look at NYC. Back in May, roughly 5% of the population of NYC had moved out, and its been a few months since then. Again, don't live there, but I've heard its now above 500k people that have moved out.