CC is not a debate forum, as we are regularly reminded, so the fact that your beliefs are not constantly refuted/disagreed with doesn’t not constitute general acceptance of your premise.
Several people disagreed (and continue to disagree) about whether your criteria produces “optimal classroom rigor”. That’s not something to be objectively measured without a lot of variables being identified and agreed upon - which has not happened to the best of my knowledge.
What I have seen said by many of the people who’ve disagreed with your premise and belief is that there are many roads to Rome. Families should seek out the schools that provide the path they think is optimal.