The Django middlewares have been made async-compatible so they only use a thread on the way in and out, rather than keeping it open the entire request, but they’re not fully async.
Full-async mode allows as many requests per thread as your CPU can handle, but it’s still the case that if you bring a sync middleware in that’s totally incompatible that it takes one request per thread
(Python forces that on us). With the async-aware middleware that’s still running things in threads for handling requests/responses, though, I think it should be able to fit quite a few requests per thread, but I’d need to go check.