Assuming you have perfect recall, and answer all of their questions truthfully, it will still take time for them to troll through all of your memories and actions.

They can do the same with a telephone / laptop in minutes.

Answer two: perfect recall

You can't recall everything perfectly, and you don't write everything down. So after a while, they won't have anything to go on. "What did you do in Thailand last Wednesday?" ... "I dunno, I got drunk with my friends?"

Versus "we searched your phone and you took pictures last Wednesday of someone who looks underage. Please turn around for the handcuffs".

In general, I have everything to hide from state actors with near-infinite resources, zero accountability, a deep understanding of the law (i.e. how to get you for almost anything), and their own personal agenda to push.

They should need to prove to me why they need to look at my stuff.