That's the joke.

The article is intentionally being arch by using "welfare", a word that's usually used to refer to programs that give to the poor to refer to one giving money to the rich. It's making the point that "government handouts" are reviled when they go the poor, and accepted relatively uncritically when they go to the rich

California's Proposition 13 law (https://en.wikipedia.org/wiki/1978_California_Proposition_13) "locks in" property taxes on homes at the time you purchase it. Most other states do not do this, the value of your home is re-assessed annually, and your property taxes are based on the current value of your home.

In general, home values have consistently increased, year-over-year, in California. This means that many people pay less property taxes than they would if California didn't have its unique Prop 13.

Many people feel that this is an unfair law, as it largely benefits people who are _already_ financially established.

This article satirizes the situation, by framing the law as an intentional 'welfare program', rather than a tax break with unintended consequences. Part of the humor is that this 'welfare program' benefits the wealthy at the expense of the poor, contrary to how we typically think of philanthropy.