"How much money do you make?"
In 'utopia', this is at worst an entirely innocent question. A bit of mild curiousity. Even better, if you don't make much, the utopianist now knows that he should keep an eye open to the possibility of offering you any help you might need.
You make a lot? Perhaps you own a lot of neat toys and have a cool house to invite people over to for parties and so on.
If nothing else it's just a bit of information. People who do such and such job make good money. Perhaps I should look into a career change?
In dystopia this is a wildly inappropriate question. Why? Because if the person doesn't make as much money as the questioner, the questioner will then judge them as beneath them, reducing their interaction to an incredibly crude materialistic competition. And if the person makes more than the questioner, the questioner will be jealous and who knows? possibly try to rob them?
Really those are The Reasons it's an inappropriate question to ask in this world. In this dystopia. Although if you ask someone in this dystopia why it's an inappropriate question, chances are very good they won't be able to say other than it's just inappropriate. Or 'it's private!' They don't even hardly really know why. They just know that you ask, and they feel fear. They feel offended by your invasiveness.
The default is fear, don't you know that?
It's private!
"What do you do for a living?"
A bit of small talk? A way to break the ice at a party? As often as not considered the same as asking how much money someone makes. Again, the default is fear. Stay away! Keep your interactions meaningless. Talk about the fucking weather. Make a stupid joke. You're not supposed to be collecting information you could use against the person. Just don't even ask questions! Just fucking sit there and shut up. Or, 'we've certainly been having nice weather lately.'
'Oh, why yes we have, haven't we?' (SCREEEEEEECCH!! THIS IS FEAR! THIS IS THE DYSTOPIA. YOU ARE A POSSIBLE ENEMY. Perhaps over the course of some very long time span I'll quit considering you an enemy. If I'm single and you stick your penis in me. Otherwise, really no need to take any chances.)