Teaching that math problems have a correct solution ("1+1=2") is considered racist by some, because… I can't tell you, because I didn't understand that when it was discussed some time ago.
Maybe someone else remembers the structure of the argument and can provide an explanation?
This keeps coming up; I can't be bothered to find all the resources yet again on this, but a lot of reporting on this was bullshit. I should probably write an article about it so I can just link it.
What the text actually said was that a focus on "getting the right answer" was bad math education, and that you should focus more on the process, methods, and actual teaching understanding, rather than just "the right answer". You can teach a monkey to "get the right answer" by just applying a few tricks, but that doesn't mean the monkey understands math. Anyone with an interest in math will recognize this is just good math education.
Now, I do have gripes with that paper because it was also filled with really odd usages of "white supremacy" and the like that were completely misplaced; it seems like a really odd lens to view things through. I guess that's the "CRT" aspect and I don't understand at all where the authors are coming from with that. But if you ignore that then the actual advice with regards to math education was pretty solid.
It most certainly wasn't "have a correct solution ("1+1=2") is considered racist". Find the text. Read it. It's really not as bad as certain outrage sites would have you believe (again, there are aspects to criticise IMHO, but not this).
But not new, either. As you say, it (https://equitablemath.org/wp-content/uploads/sites/2/2020/11...) is CRT sauce poured over non-controversial advice on teaching.
That, IMO, makes it dangerous, as it associates CRT with things everybody will agree to be good, indirectly instilling (or at least trying to do so) the notion that CRT is good.
What's important is in the concrete specs which textbook makers, curriculum designers, and other industry stakeholders will target and respond to. And under the Equitable Math program, there is simply no spec for, say, Algebra in middle school. That's what industry stakeholders and textbook writers will see.
The actual training teachers are receiving is that there are many ways to teach things like long division, and insisting on only using one method is not useful to students.
As an example, when teaching multiples of 9 you shouldn’t just use rote learning but point out the internal checksum of multiples of nine (add up all the digits to get a single digit and you get 9, for the simple tables the first digit will be 1 less than the number being multiplied, so 4 x 9 is 36, 3 + 6 is 9, 5 x 9 is forty-something so working backwards 9 - 4 is 5, so 4 x 9 is 45).
In addition there’s the “times ten minus one” method: 3 x 9 is the same as 3 x (10 - 1) so 30 - 3 is 27 (and add up the digits to make 9).
Teachers need to be allowed to use multiple methods of instruction, and restricting them to only exactly what is in the syllabus is racist because then the only people who get the quality instruction are the rich who can afford out of school tutelage, ie: predominantly white populations due to institutionalised racism in the USA keeping non-white populations poorer than their mostly white neighbours. Yes, there are white people living in poverty but when you compare white to non-white populations in the same region they are still better off.
The shorthand in the USA is that any policy which keeps poor people from success is racist because the rich/poor divide in the USA is predominantly along racial lines.
As for the difference in outcome of white vs non-white in poor neighborhoods, I feel there are more at play than institutionalized racism, but it is incredibly difficult to have a nuance discussion on the topic.