We have a really strong presumption against what's called a prior restraint. It means you generally can't stop someone from publishing something, but you can sue them after.

This does two things. First, it makes it so that if someone feels strongly enough that they're right to be willing to risk the penalty, the public still gets the information. This is important. It's a check on the courts getting it wrong.

And the second is that in order to punish someone for speech, you have to prove it in court in a public adversarial proceeding where the person being punished has an opportunity to defend themselves and the claim is aired as part of the court record in a context where everybody knows that it's in dispute but the media and any interested party still gets to find out what it is.

This is obviously not what happens when you implement a general prohibition against all claims of election fraud with no meaningful opportunity for anyone to view the material being censored or make their case that it shouldn't be prior to its removal.