I don't have much experience with this kind of thing, but from here it looks like a program written this way would be nearly impossible to reason about performance when something as simple as a function call in your Python interpreter can have wild fluctuations in predictability just due to underlying network latency, remote host saturation, etc.

It seems like you would need an entire observability framework built and instrumented on top of this to ever really be that useful.

To be clear, not all of your coroutines become distributed. You explicitly declare what you want executed remotely, and you'll probably want your workers running in a VPC - it's just a nifty way of scaling your app horizontally without sinking too much effort into how you choose to define your distribution boundaries. It wouldn't be any different than scaling any other service horizontally using something like Kubernetes (which is probably how you'd manage wool workers as well).