Isn’t there a high probability that there is plenty of evidence to support that “idea” and that they would only have to look at the performance of the incoming freshmen or the constant cries by educators for remedial classes. That or simply compiling accounts such as the one posted by the OP.
This is not about casting aspersions and it does not help to blame the teachers or the parents. It should be about finding solutions to a problem that is simply getting bigger by the decade. This will not happen until the next generations collectively call for changes because the former ones are quite happy to believe in the fallacy of the Lake Wobegon kids. Our current system is no longer a highly performing one as evidenced by FOB kids who come to the US with huge handicaps in English catch in no time and leave their peers in the dust. Feel free to track down the tools they rely on and perhaps see that they hardly rely on your daily classroom to compile their better records.
If the free school is not the problem, it surely is not the solution. And by a mile and a half.