The format change should be: no disparaging preambles to moderator questions.
Example:
President Trump, what health care plan do you have ready to replace to ACA, if you overturn it?
NOT:
You have no comprehensive alternative health plan.
Your EO on preexisting conditions was largely symbolic.
If the moderator chooses to fire off preambles like these in a lead up to a question, particularly when aimed at one side and not the other, then the president should get to interrupt with a rebuttal to each one, as Trump rightfully did.
Totally agree.