Colorblindness was a psyop propagated against white peoples in order to destroy them. The goal was to disarm white tribalism while maintaining racial and ethnic tribalism for everyone else.

I think there were enough people for whom the ideal of colorblindness was sincerely held belief that had there not been a conscious effort to push the most extreme supremacist elements, and a narrative to convince people that their beliefs had validity (well, unless they were Cis White Men) that average Americans would have banded together against these groups and ideologies, and they would have died down to insignificance.

Colorblindness may have been part of a manipulation campaign, but so long as the ideal can be enforced in some way (that is, making the outgroup based on who forms ingroups based on racial lines and punishing them for it.) I believe you could probably make a functional society based on that ideal.