Forget the fact that his public statements can cause real damage to the targets of his accusations.
The gag order is called for if only to ensure he receives a fair trial with an outcome determined by an untainted jury. Whether he is trying to or not, every public statement potentially removes jurors from the pool by having them create a predetermined opinion on the defendant and the case.
This is literally a case where the judge needs to “protect the defendant from himself” as well as protect the proceedings from a mistrial or future appeals.