It is not about serial ordering. The coroutine code looks the same as the synchronous code. While using GCD blocks, you can still end up with callback hells. Ho

It is not about serial ordering. The coroutine code looks the same as the synchronous code. While using GCD blocks, you can still end up with callback hells. However, you can, do nicer things with GCD when build on top of https://github.com/google/promises https://github.com/google/promises, but that is outside of the linear code execution discussion.