A couple ideas:

If you don't like privacy then you don't need curtains in your house.

Ask them to unlock their phone and hand it to you. Most people will balk.

One thing to think about is that some people don't mind losing their privacy to the government or a corporation but they do care about losing it to real humans that know them. As an example, if a husband is cheating on his wife he doesn't care if the NSA or Big Tech knows about it because they (most likely) won't do anything negative with that information. But he would want to keep that information from people he knows because they may use it against him and will definitely treat him differently by having that knowledge.

Food for thought.