This is not true.
First off, I encourage people to pay taxes & be forthcoming.
Yes the blockchain is a public ledger, but this is a good thing, because it prevents exactly the kind of cheating you mention in your comment above. The ledger is secure because it is governed by math, and we know that the laws of math are immutable. In other words, they cannot create crypto out of thin air and no one can touch your crypto without your private "keys" even if they can see the balance in one of your wallets via it's public address. Your crypto wallet cannot be seized, like your bank account can.
As for privacy, there are sectors of the cryptocurrency market delivering this valid feature. Monero, XMR, is one of the privacy coins. Z-Cash & BitcoinDark are others. I believe Dash offers a certain level of privacy as well.
There are well over 1200 crypto assets existing at this very moment, with under 800 at this time a year ago. The genie is out of the bottle and ideally crypto will enable the ending of the Fed's reindeer games.