There's scams with fiat currency, but you don't show that as evidence that dollars aren't ready for mainstream. When people get scammed out of their crypto it's not blockhain's naivety, it's the victim.
Edit: you all are comparing money, banking, AND government regulation to crypto. They are not comparable and that's not a fair comparison. Crypto is a ledger, like QuickBooks or bank accounts. I'm not even arguing that it should have a great value, but technically it does have value and it serves its purpose. Crypto is only like 15 years old.