Privacy on the blockchain is more than a necessity, since the inception of blockchain technology, transactions have been more secure, but easily accessible to prying eyes, take the recent binance hack as a major example, do you have the idea and amount of patience , the hacker must have had in order to pull that off,first he would have needed to study the wallet in order to know the amount of btc contained in it and all, take a privacy coin for example, it wouldn't have been able to be possible because privacy coin like veil, deletes transaction history once a transaction has been completed thereby offering more security.