This is a familiar pattern. A court finds that there's a constitutional issue with a law and, as it must, throws out the law rather than writing a new one. This is correct: you generally don't want your judicial system in the business of making up new laws and regulations. (Yes, the line between interpretation and making up is thin, but it's still a good line.)

People with an axe to grind (on either side of the political spectrum) immediately act like the court made it impossible to even consider rewriting the law. Nuances are lost. The world is ending.

From the letter, quoting Malcolm Gladwell: "Take a random group of 8-year old American and Japanese kids, give them all a really, really hard math problem, and start a stopwatch. The American kids will give up after 30, 40 seconds. If you let the test run for 15 minutes, the Japanese kids will not have given up. You have to take it away."

From the court decision: "There were reasonably available alternatives to the MPT that on their face appear to be less impairing and at least as effective in achieving the goal of improving student achievement in math. These include requiring a minimum number of hours of math instruction or a math course in B.Ed. programs, requiring an undergraduate math course as an admissions requirement for B.Ed. programs or waiting to see the effects of the other parts of the Respondent’s four-year math strategy."

Unfortunately, the author is more interested in giving up than solving the problem. The productive action would be to say "Hm, OK, the court gave us a list of practical alternatives which stand a good chance of passing review, so I'm going to start advocating for one of those."

In fact, the court notes that "Research from the province of Quebec, where student math test scores are high relative to the rest of Canada, attributes that province’s student achievement to 'a uniquely strong emphasis on requiring trainee teachers to undertake more courses in both mathematics methodology and mathematics content.'"

That seems promising! Requiring trainee teachers to take mathematics courses is even one of the ideas the court recommended.

Ah well.

The full court decision is a good read, by the by. The court thought hard about this, and balanced quite a few factors. The reasoning behind the decision is laid out in great detail and there's certainly enough there to engage with if a critic wanted to do so. The author of the letter does not actually address the court decision at all.