Cryptocurrency is missing one key feature that hasn't allowed it to become an acceptable medium of exchange among the common folk: **privacy**. People generally don't want to have their balance and transactions exposed to every single party they interact within the blockchain.

Yes, blockchains like ZCash and Monero exist. But they fail to address 2 important problems: Regulatory auditability and smart contracts.

Regulatory auditability

Crypto exists in a regulatory gray area in many countries. Especially in the case of privacy coins, regulatory bodies have grown wary of these black-box chains as they practically make all transactions untraceable. They create(d) a breeding ground for money laundering, tax evasion, and other illicit activities. I experienced this first-hand when my wallet got emptied because of an exploit. The investigation was halted once the police discovered that my coins were funneled through a privacy chain.

If a chain is able to implement programmable privacy, it would attract both institutional and retail users as privacy becomes a choice, not a luxury. Public institutions can choose to show their transaction history, users can choose to hide their personal transactions, and regulatory bodies can track criminals by requesting access from the creator of a token or the owner of a smart contract.

Smart contracts

Another very hard problem to solve is deploying smart contracts on a privacy-centric blockchain. The reason is that smart contracts depend on some transparency to function reliably.

Transfers are simply not enough. Web3 needs smart contracts to be able to deliver true value. Afterall, it's what made Ethereum so popular. Addressing the smart contract shortcoming in privacy chains will allow them to flourish and go beyond basic functionality.

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