I don't think this is a fair characterisation. I have never heard of anyone wanting to stop this. If you mean CRT, that is something different, or at least the versions of it that are causing pushback are different.
More broadly, books like Lies my Teacher Told Me have pointed to the long history of numerous failings of our history curriculum.
We never got to be anywhere near the slave quarters, and it was never once mentioned that dozens of black people were brutally slaughtered there with their heads put on pikes at the entrance.
There has never in the history of the United States been a curriculum containing CRT at the K-12 level because children don't have the background and capacity to understand it.
And by bringing it up at all, you're proving that you don't either.