It’s a big mess: because they can’t reliably raise money through property taxes, local governments have turned instead to sales tax, fees for various public services, long-term debt, sale of public assets, money handed out by the state government, and various budget shenanigans. School bonds in particular require only a 55% majority to pass, and then can be paid back via property taxes, so those have been popular in most CA cities, even when they probably aren’t the most sustainable way to raise money to fund school facilities.

The politics are complex, because Prop 13 bundles together several loosely related provisions. “Low taxes” and especially “make sure the legislature can’t raise taxes whenever they want” is a generally popular message, but there are demographic/political reasons that it has stronger support than just that. For instance:

(1) Freezing tax rates at purchase time is a net transfer away from renters, new people moving to the state, young people, new home buyers, etc. and to older, richer homeowners (as well as corporations and very large land owners). For obvious reasons, the latter more often have the right to vote, more often vote in practice in elections at all levels, have more money to spend on lobbying and campaigning, etc.

(2) The current demographics of statewide popular elections are different than the demographics of the whole population of citizens or residents, as represented by the state legislature. Seats in the legislature are apportioned by population, which means that urban areas which make up most of the population of the state and tend to vote for Democrats are favored. By contrast, conservative voters tend to vote more often in statewide elections. By forcing supermajority legislative support for tax increases, Prop 13 gives folks in the conservative minority a sort of veto power, which they are loath to give up.