Clearly, if anything, we should have more random stops and searches, maybe even in the streets. That would catch more of these dumb criminals.
My response was trying to say that he's way off in his understanding of what people of average intelligence do when they do criminal things. There are plenty of arguments one can use to make a plausible case against widespread border searches. The argument that basically no one is dumb enough to carry a phone or laptop with incriminating data across the border is not one of them.
Invading everyone's privacy to catch a few dumb criminals (because all non-dumb criminals would have just sent their data through the internet) is a really really bad tradeoff, because the cost:benefit ratio is too high.