... The issue didn't develop overnight, it's not getting fixed overnight, but public schools, colleges, local school boards, many parents and many teachers aren't doing anything to fix the problems. ...
IMO, the problem with Math began at least in the mid 1960s when the "New Math" fad became the standard Math curriculum. The old methods, which worked, got shoved aside for something believed to be less boring, but was confusing and less simple. Parents, who knew how to do the things supposedly being taught, could not figure out the process being taught.
The failing "Look-Say" word-memorization method of teaching Reading, which has never been @#$%-canned for what actually works, Phonics, came into schools' curriculums in the 1950s or 1940s.
Why Johnny Can't Read, which called out the method's failure, was published in 1955!
Too many school educrats are part of the problem. Colleges' "Education Schools" feed and perpetuate the problem. Teachers unions fund their puppets' board of education campaigns. Too many parents are caught up in, "My kids' school isn't
that bad," thinking and don't pay attention.
Private school tuition is expensive, and homeschooling means (over-simplifying some) being a single-income family, not easy to do in the US. Unions keep their shills on school boards, and have members who will retaliate against the children of parents who dare to "cause problems".
Changing all that into an actual system that educates will be a revolution, IMO.