Earlier quoted context omitted.
What if you invert your thesis. Sooner doesn’t necessarily imply “higher standard”: 1 - American school teach the alphabet before grade 1, and push kids to read early. German schools don’t even teach the alphabet until grade 1' yet by the end of that year the reading level of the kids is the same as US kids at the end of grade 1, or better. German Pädagogin justify this by saying there is some neural development issu…
Wealthy parents will still define higher standards, because they will send their kids to private schools where more advanced math is taught (e.g. Phillips Exeter Academy teaches calculus to all students and offers linear algebra, statistics, and discrete math to advanced students.[1]). Instead of opening up opportunities for all the kids, this will ensure that no poor student can compete because the courses won't eve…
As you mention, poorer students are denied the opportunity to take more advanced classes. But even those who do are faced with a massive disadvantage.
See, top tier private schools shamelessly pass students unwilling to actually learn [1]. These same schools and parents subsequently leverage connections, wealth, etc. to insert their students into prestigious schools...where they continue to not learn math (and ultimately are hand-held to high-paying, white collar jobs, but that's another story)
Net result is unfilled higher math seats filled, and with that less math competence across society. Fewer thinkers advancing our perspective, etc.
Opportunities to access these materials is key, but providing consistent standards is just as important. If we can't do that with math, where?
[1] prior work with NE boarding schools, witnessed the contortions these institutions would go through to pass / give top marks to obviously unqualified students.