Interesting that the distinction between phones and boats was not enough to dissuade whatever point it is that you're trying to make.

From Chief Justice Roberts in Riley v. California: "One of the most notable distinguishing features of modern cell phones is their immense storage capacity. Before cell phones, a search of a person was limited by physical realities and tended as a general matter to constitute only a narrow intrusion on privacy."

The same is true at any border crossing - you have to submit to searches by CBP agents, who don't need any probable cause. I believe device searches are still a somewhat greyer area, at least if password protected (as providing a password would be compelled speech, unlike a luggage search which can be conducted without any action from your part).