You are technically correct, however the same logic applies to every type of enforcement.

Ideally the enforcement of every rule should apply to everyone equally, but in practice we see the police behave differently towards different people, we see tax audits and penalties applied mostly to people without the means to defend themselves and we see how apparently the law and government rules don't even apply to Trump. The world still goes on and we somehow deal with all of this.

Twitter enforcing their own rules is just going to be more of the same.