No that’s not true. Only 50% of school funding comes from property taxes. The rest comes from federal and state sources that make up the gaps in property tax revenues. More states have progressive school funding (poor areas get more) than the opposite. (In the vast majority it’s +/- 5%.)

This is why liberal think tanks have shifted the goal posts to “equitable funding”: https://www.brookings.edu/research/how-progressive-is-school... (“ Someone expecting to find widespread evidence of “savage inequalities” will be pleasantly surprised to learn that, on average, poor students attend schools that are at least as well-funded as their more advantaged peers... But there are good reasons to believe that it is more expensive to provide the same quality of education to disadvantaged children—in other words, funding that is equal may not be equitable.“).

Which, to be fair, I don’t think is a flawed idea. If everyone can acknowledge that there isn’t a funding gap, we can have the conversation that poor kids actually need more money to even out inequalities.