"The right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated, and no Warrants shall issue, but upon probable cause, supported by Oath or affirmation, and particularly describing the place to be searched, and the persons or things to be seized."

If Prosecutors obtain a warrant for access to these papers and effects, then Apple should help execute that court order.

As much as I don't believe or trust Trump on anything, ever, in this particular case he's not wrong, as long as a warrant has been issued by a court of law.