What Kirk espouses was once stated "the soft bigotry of low expectations," which is something of a valid concern with any program that offers an advantage to the disadvantaged. As bullshit as most "bootstraps" arguments are, there are kind of a shitload of freeloaders on programs like SSDI, so that point is at least arguable.
But in the context of civil rights, it ignores the fact that blacks in particular, at the time of the Civil Rights Act, weren't merely disadvantaged, they were excluded. And God knows how much longer they would have continued to be excluded.
Particularly germane to Kirk and the Civil Rights Act, the first black commercial airline pilot, David Harris, was hired by AA in 1964. What a coinkidink. And he was qualified after being a Captain in the USAF after being rejected from AFROTC twice on racial grounds. https://en.wikipedia.org/wiki/David_E._Harris
So, it was only the military efforts to integrate, which preceded the Civil Rights Act, that produced the first black pilot.
So even what might be considered Charlie Kirk's broader point about "DEI" while seeming at least arguable, is still bullshit.