This 'flawless argument' is an irrelevant statement, we have given blockchain technologies over 15 years to improve, but the scams have been getting bigger in an unregulated environment.
I also don't recall any regulated bank accounts getting automatically drained or losing everybody's money due to a single scammer or a bad actor.
One single error or exploit in these smart contracts results in millions being drained. This happens on a weekly basis with a giant lack of consumer protection, unaccountability or any chance of getting your money back (which that is a huge unsolved problem). So yes, these smart contracts do not work.
It's a system designed to fail with thousands of disasters, rug pulls and scams just waiting to happen.