A special ed teacher who had been working for decades and who knew many students who had been held back told me the same. Even as adults these students would tell him that things had been going okay until they had been held back. One administration hinted at doing the same to one of our kids because he didn’t speak English at an academic level, but we worked our asses off to bring him up to speed in a matter of months, and the same special ed teacher told us that parents don’t actually need to hold their kids back if they don’t want to (something the principal failed to mention). Soon enough our kid was reading, writing, and speaking at his grade level (which he’d already been doing in his mother tongue) and the principal acted like she had never even suggested that she wanted to hold him back. And shit like this could have ruined his life! School is already difficult enough without every figure of authority telling you you’re too much of a fuckup to advance with your friends to the next grade!