From Wikipedia:
Critics of CRT, including Richard Posner and Alex Kozinski, take issue with its foundations in postmodernism and reliance on moral relativism, social constructionism, and other tenets contrary to classical liberalism.
Now that is beginning to make some sense as to why Trump would claim something.
Here's more:
Judge Richard Posner of the U.S. Seventh Circuit Court of Appeals has "label[ed] critical race theorists and postmodernists the 'lunatic core' of 'radical legal egalitarianism.'"[37] He wrote:[37]
What is most arresting about critical race theory is that…it turns its back on the Western tradition of rational inquiry, forswearing analysis for narrative. Rather than marshal logical arguments and empirical data, critical race theorists tell stories – fictional, science-fictional, quasi-fictional, autobiographical, anecdotal – designed to expose the pervasive and debilitating racism of America today. By repudiating reasoned argumentation, the storytellers reinforce stereotypes about the intellectual capacities of nonwhites.
So...that's more explanation than what has been given to date.
Jeffrey J. Pyle wrote in the Boston College Law Review:[40]
Critical race theorists attack the very foundations of the [classical] liberal legal order, including equality theory, legal reasoning, Enlightenment rationalism and neutral principles of constitutional law. These liberal values, they allege, have no enduring basis in principle, but are mere social constructs calculated to legitimate white supremacy. The rule of law, according to critical race theorists, is a false promise of principled government, and they have lost patience with false promises.
That's pretty bad...
All this is reminisce of the Nazis attitude towards the Jews. That kind of hate speech is illegal in most countries around the world.
I've witnessed real racism...
And where a claim can be made for classism or that a caste based society is evolving in America it most certainly is not based upon racial lines. And I've witnessed plenty of people who have elevated themselves out of their caste in remarkable ways to remarkable ends.