You assume too much. Our current systems evolved over millennia. Cryptocurrency is less than 10 years old. Nobody thinks the current state of the tech is what everyone will end up using, where you have to write your own smart contracts using an inscrutable smart contract programming language.
Nevertheless, having an impartial, inherently trusted computing base is a promising foundation. What you then need on top is various forms of static analysis that make smart contracts scrutable by mere humans (and preferably writable by mere humans). That's how you collapse the complexities and largely eliminate the need for centralizing risk and analysis.
Edit: it's like you're expecting people to do word processing using punch cards. That's where cryptocurrency tech is right now, and the more mature programming and UI/UX of today is where we should expect it to be in 10-20 years.
Nevertheless, having an impartial, inherently trusted computing base is a promising foundation. What you then need on top is various forms of static analysis that make smart contracts scrutable by mere humans (and preferably writable by mere humans). That's how you collapse the complexities and largely eliminate the need for centralizing risk and analysis.
Edit: it's like you're expecting people to do word processing using punch cards. That's where cryptocurrency tech is right now, and the more mature programming and UI/UX of today is where we should expect it to be in 10-20 years.