[tomchristie]

> It's threaded vs async/await

Fair enough, sure.

> lack of backpressure

You’ll get new calls into the application on new requests, yes. Request bodies are pulled tho.

You can perfectly well ensure that server implementations properly handle flow control, and if necessary also have a configurable number of maximum concurrent requests.

Either way, those sorts of concerns would be far better addressed by having server implementations against a common interface, than by framework authors having to handle (and continually re-implement) the nitty gritty details of high/low watermarks and pausing/resuming transports.