Public Privacy

So we were discussing privacy on steem blockchain then a scenario played in my mind where everyone use only steem blockchain, let's say it is compulsory. We know how social media has turned us into a global village of stalkers but with that, we would not be able to lie about how much we have in our wallets or whom we sent money to. For instance,

Guy: I am super rich, I will give buy you only the most expensive things.
Girl: Really, what's your steem username, I just want to follow you.
Guy: Urm...