I don't agree any of those things should be taught in 3rd-5th grade because I think it is much more important to exercise the fundamentals of critical and creative thinking, logic, imagination, etc. at those ages.
I also have a big problem at any level of schooling with these unscientific and unproven "theories" (if you can even call them that) being taught by people who have entirely bought into the cult thinking and have no ability to critically reason about them let alone the desire to.
Would lessons about socialism and collectivism teach why the system can generally only sustain itself at a state level by devolving into a single party police state dictatorship in which the people most certainly do not own the means of production? Doubtful.
Would the teaching of CRT expose it for the unproven religious-like propaganda that it is? Or would it teach the horrific hurtful and racist pseudoscientific lies about toxic whiteness or children bearing some responsibility for things done by other people due to their race? Probably the latter, right?
It's like inviting a white supremacist to teach children lessons about nazism. Or a creationist to teach biology. Or a flat earther to each geology. Not a helpful lens at all.