Not posting your porn online because you're afraid someone will find out surely isn't a dystopian future.
The particular problem the author mentioned was marriage. It's a kind of fraud to fool someone into marrying you by not revealing things that they wouldn't accept about your history no matter how unreasonable their judgement is. You're taking advantage of their ignorance to gain more for yourself at their expense. A potential spouse has every right to dig into any aspect of your past that they want because committing to the wrong partner could ruin their life. It's only a good thing for them to be fully informed.
One other aspect of privacy is that it's harder for people with power to control other people's (private) behavior. For example, if all location information was public, employees would be much more likely to face repercussions at work for interviewing at other companies. You can make it illegal but it's hard to prove and will certainly still happen, so privacy is more effective. It's the same sort of reasoning behind secret ballots.
There is plenty of acceptable behavior that people, quite reasonably, don't want to be tracked or widely known.
> The particular problem the author mentioned was marriage.
I understand. I was speaking to a larger point, not about this problem in particular.
Things like my physical location, what I'm buying at the store, what medications I'm using, and so forth. Honestly, the list is extremely long.
A similar thing could be done for scraping images and doing face recognition. It only takes the political will.
I'm not saying that you're wrong here. However, the effect that you're describing leads directly to a dystopian world that few people would actually want to be living in, and the only thing that an individual could do about it is to withdraw from society entirely, including never going out in public.
There has to be some way of preventing that.