CRT has nothing to do with teaching history. CRT uses history to justify support for many of its tenets.
CRT is an offshoot of the Marxist-oriented "Critical Theory" of oppressed and oppressors. CRT is a theory that views the world through the lens of power relationships and societal structures based on group identity rather than a world made up of individuals.
One of CRT's many tenets is that outcome alone determines if something is racist. It espouses that giving everyone equal opportunities (equality) is racist unless we have equal outcomes (equity).
It totally ignores an individual's talents, intelligence, motivation, physical abilities, or cultural values but rather focuses on systems and institutions to explain outcomes.
In my opinion, this is where CRT is dangerous for society. You cannot ignore an individual's god-given talent, their physical abilities, nor increase a person's intelligence. Therefore, the only way to ensure equity is to bring everyone down to the lowest common denominator. That is why you see school districts ending gifted student programs, lowering the standards required to graduate, and not disciplining unruly students, all in the name of equity.
Rather than try and get everyone to reach their individual best and accept that not everyone will be successful or perform at the same level, they try and develop a system where everyone archives the same level of mediocracy.