You may not be able to practice discrimination legally, but in your heart and mind you can be whatever you want.
When you take that away from people, they no longer feel free, and they will retaliate like a caged animal.
Whereas groups of people can get together and decide to boycott whatever they want, government officials cannot direct such activities. That's the right to free association and expression protected by the first amendment. The only way you're ever going to get rid of "cancel culture" is if you remove that right. If people can't decide for themselves what they want to buy, and if they can't decide to associate with similarly minded people, there is no first amendment right to free speech.
And as bad as everyone says cancel culture is, no one has proposed a model where free speech is maintained yet cancel culture is forbidden. Most models proposed to are explicitly anti-free speech. The rest are just fascist, which incidentally that's the plan this administration is going with. So congrats, maybe you got rid of cancel culture, but you took down the first amendment with it.