So this data can fall into the wrong hands by selling data by the exchange or hacking it by hackers, for example.
Others, we are to some extent dependent on third parties, which is not acceptable in cryptocurrency, in my opinion.
You can still buy and sell bitcoin to people in your city or use ATMs (2 first things that come to mind). Privacy totally depends on the user; it's easier to trust a third party to manage most of our operations; but at what cost? Google stores our password if we allow it, and then fills the user and password fields automatically. It's fast and convenient; but at what cost?
I'm aware the situations are not 100% identical, but I don't think it's a bad comparison