All it takes is some API calls and some simple python scripting and you could data mine a person. Maybe they subconsciously only upvote LGBT posts. Maybe they downvote leftwing posts.
Then, oops, one day they post something that can doxx them and now they’re getting targeted ads or worst case a stalker or someone who wants to get them fired/thrown in jail.
Now imagine a machine learning algorithm or AI has done all the data mining and it took just a couple days to work through all users on lemmy.world.
If there’s any data that could be used to make money someone will eventually try it.
I keep ear plugs in my zip pouch wallet so I’m always ready for any concerts or random loud areas.