No, I don't think this would simplify anything. There is no real advantage over using promises and async/await. Understanding the difference between the two syntax styles that ostensibly would do do the same rather make everything more complicated and inconvenient.
You seem to suggest that removing the state machine and value encapsulation would be beneficial - I see only disadvantages in dropping these features and introducing an incompatible alternative. If you think there's a performance limitation, I'd rather allow better compiler optimisations for async/await code.