Some variation of the below:

Can I have your phone with the messaging apps unlocked?

Can I log into your personal email?

Can I see your tax returns?

Can I set up cameras and microphones in your house?

Can I place a GPS tracker on your car?

Saying you don't need privacy because you have nothing to hide is the same as saying you don't need freedom of speech because you have nothing to say

"Arguing that you don't care about the right to privacy because you have nothing to hide is no different than saying you don't care about free speech because you have nothing to say." - Edward Snowden

https://en.m.wikipedia.org/wiki/Nothing_to_hide_argument

Ask to watch them pee. When they say no, ask what they do when they pee that they don't want you to know about; that is the only reason they could want privacy, right?

"Okay, then hand me your phone unlocked and give me as much time as I want to poke around your browser history, files, and photos."

Medical privacy is a great example.

Consider a situation like Texas right now where abortion went from a normal, legal thing to something that you can be fined and jailed for.

Would such a person be OK with the state having access to their medical records so they could jail or fine them?

People need to understand that much of privacy precautions are "layers" of security against "what if" scenarios that can sometimes be very real.

"Sweet let me see your search history. I've always been curious what your taste in porn is"

"well, let me come over to your house uninvited and walk around the rooms looking through your personal belongings".

I take out a pad and pen, "what's your bank credentials? Also, your [social media] credentials? I won't use it against you. Promise. ... No? I thought you have nothing to hide?" I put the pad away, and hold out my hand, "let me see you phone. I want to look through your pictures and internet history. ... No again? Huh. I guess you do care about privacy."

I usually ask them for their phone

That's about all there is that we can say, some people just don't care about their privacy until a blatant violation of it is right in front of their face, and nothing else except for that would ever make them care.

The energy is better spent on sharing info with people who want to do more for privacy, so that eventually it's hopefully normalized to care about privacy.

Giving up your right to privacy because you have nothing to hide is like giving up your freedom of speech because you have nothing to say.

Ask them if they poop with the door open.

I guess they think they have nothing to hide, because they don't know, or don't care about, how their own information can be used against them.

Because it doesn't happen in an obviously invasive manner, they don't think it's a big deal. It's harder to associate an abstract concept to actual value.

That’s a choice they can make for themselves, not a choice tech companies and governments should make for everyone. If they want to trade their privacy, and I don’t - fine. All I want is the power to choose and know that choice will be respected.

I usually ask them to hand me their phone while its unlocked and that really makes some people think. Its funny because at the same time i have so little to hide that the only reason i have a passeord on my phone is because it makes stealing it harder. But im not gonna hand my data some random company just to watch braindead 30 second videos.

Gotta hit them with the "oh cool so let me see your phone and browsing history then"

We're entitled to a reasonable amount of privacy, such as locks on our doors and curtains on our windows, why shouldn't reasonable privacy also apply to our lives online?

I have a friend / colleague who was a bit like this. It is a "see it to believe" situation. For her it was when she was at work and she watched her mouse stat moving on its own.

When she thought about how she never did anything bad on her work computer, but sometimes accessed her personal email... She got it.

And now she pays closer attention to things. Like in our city you're pinged via WiFi when you get on a bus, but you can opt-out or jut turn of your WiFi, so she does that. And she makes email aliases now too. Nothing too serious, mind you, but she is 50 and figuring this out on her own and then teaching her friends and colleagues about it which is way better than going down the rabbit hole. Now there's a bunch of boomers refusing to use Teams or access work email on their personal devices because she explained that they do have things to hide: the names and ages of their children and grandchildren, where they go for drinks after work, what they watch on YT, etc.

I don't get into it with people though. People just write me off as some nerd, which is not the case.

Depends on the person, but sometimes things such as:

"Is there anything you do, watch, listen to, say or have done in the past, which is currently illegal in another country?"

"Did you see how in the US, some states have just recently made abortion illegal, and in others, you can get in trouble with the police for wearing clothes which they don't think match your birth gender? Both things were perfectly legal a few years ago"

"Imagine it's 2024 and mandateless unelected UK Prime Minister Rishi Sunak says model railways are offensive to motorists, so they've banned them"

"Do you think Facebook's going to defend your privacy when the government makes model railways illegal, Dad?" :P

Do you have curtains on your house? Why, if you have nothing to hide?

Great and what if a dictatorship takes over and starts looking through historical data. This is a depressingly high possibility in my country.

But even going less extreme than that, what about just draconian surveillance laws. In my country they've already tried to ban VPNs fortunately they're technologically illiterate so they've been massively unsuccessful at that one. But what if they grow a collective brain?

If you saw a powerful but drunk person hit and run a child would you not report it to the police?

In the old days the powerful person would hire a private investigator to learn how to make your life misery to put you off testifying.

Nowadays they just need your internet history... unless you are fine with assholes getting away with killing kids of course.

Tell them that they don't deserve free speech either because obviously nothing of quality comes out of their mouth.

Well if you live in a democracy you should. It's not about your data alone, its everyone else's. It's social media company XYZ determining how each individual is going to vote, then, on election day sending all people on one side get out and vote messages, and sending people on the other side a tsunami of unrelated bs to make sure they don't know about the election. Or push a bunch of fakenews to make them feel both sides are the same and why even vote?

Do this in a couple key areas and you only need to hit a few tens of thousands of people to turn a presidential race.

We know it can be done because it already has been. If you live in a democracy you should care a good deal about privacy, even if you somehow have nothing to hide

I say nothing. Not my businesses. Their data. their choice. Why should I criticize their decision?

Depending on the context, I go full in:

Yes, nothing to hide and you are not the only one. Assurance companies have observed that people who masturbate are healthier. And based on your surf, you don't. So you have to pay more.

Now what do you want to do? Masturbate to pay less or ?

We all have something to hide

I would offer a suggestion "it's not that I have nothing to hide; it's that i have nothing i want you or anyone else to see".

Both may sound similar but in reality quite diffierent.

"Here's a pen and piece of paper. Why don't you write your username and passwords out for me."

It's not about secrecy. It's about privacy.

Look at this website. It’s in Dutch, so you might need some translation. https://decorrespondent.nl/209/nee-je-hebt-wel-iets-te-verbergen/23fc6e9d-f667-0377-1675-7b5e7bde60cc