The very existence of a clear transaction history on the blockchain is the root of all problems. If everything is natively encrypted by zero-knowledge proofs or ring signatures, none of the issues - privacy and chain analysis, the possibility of tainting a coin, the appearance of centralized coin-mixing services with questionable security, and the numerous aftermarket privacy tokens and coin-join protocols - would exist. The idea of a privacy-preserving digital cash has been proposed since the 1980s, unfortunately this property is not found in many major cryptocurrencies.