"I have nothing to hide."
“To hide” sounds like something active, an action, a deed. Maybe you don't want to actively hide anything.
Maybe you just don't want your device not to be active and bubble out everything it gets to know about you without your consent. That's different than hiding.
And besides, the phrase “I have nothing to hide” is BS, of course: Nobody wants to show everything to everyone (even those who post "everything" on social media just want to show what they want you to see. There are probably very few people -even influencers making a living with social media- who would permanently use a camera app that records and streams randomly without them knowing and/or pressing the record button).
Years ago, I picked up a trick from Glenn Greenwald (if you don't know him, give "No place to hide" a read or maybe this famous TED Talk ), which I use from time to time in a modified form, you could try it out, too:
Ask people, who argue that they have nothing to hide, to give you their device and all their login credentials for email, social media etc. for just 24 hs and the permission to do whatever you want to do with the information you're able to extract (perhaps with the restriction not to drain their bank accounts).
I bet you'll make the same experience i always made: Nobody ever handed me over a single device.