There are two points here
- I don't know about other blockchains but Bitcoin is public by design . Because on Bitcoin network , most of the transactions would be between big wealth funds , nation states , corporations etc .. the fees will make it impractical for me to transact on Bitcoin network . These big transactions must be in public eye .. that is a feature NOT a down side .
- as regards to tax , KYC or not , Bitcoin is an asset . We must pay the taxes as per the legal requirements just the way we pay taxes when we sell real estate or stocks . I am sure you are not promoting tax evasion. Are you ?