They're not dumb, they just know their voters are. One of the biggest mistakes people make is thinking these rethuglican politicians are stupid or poorly educated in any way. A lot of these MFs went to Yale, Duke, Cornell, Fordham, Auburn, UPenn, Harvard, Rutgers, etc. They received top notch educations often in law, business or civics. They are FAR from dumb.
But this is also why they've been pushing to demonize higher education and NOW damn near any kind of education at all. It's why they push the "college campuses have become WOKE liberal cesspools" narrative. They can't have their base seeking higher ed or learning critical thinking skills. They need those idiot voters to keep thinking coal is still a viable industry in the 2020s and that CRT is when black people exist.