From the docs:

"If your Workers application is returning an 1101 error code, your code is throwing an exception. You can catch the exception in your code using a try/catch block:"

That's great, but you end up just returning those details in a header or sending them somewhere else. We have to catch errors and send them to our backend for logging so we can debug them at a later point.

This doesn't help you debug things like sub-requests from the Worker or how they interact with other Cloudflare features like Cache.