Here's my lived experience: algebra in 7th grade, black boy. I'd have been better off taking it later, and making it up with summer geometry, trig, and precalc courses /certs in between algebra, algebra ii, calc, and diff eq/calc ii in high school. If that meant my classmates could have a better chance of keeping up, all the better; being in the historically lily-white gifted track at my magnet high school didn't do much in the way of convincing my teachers not to give up on me at the first sign of weakness. Yet another nuance you either miss or refuse to acknowledge.