Yes. And then as with that solution, in many cases it doesn’t work and you have to fall back to regular polling. If you remember to detect that the connection has dropped. And then the testing defeats the purpose because it wakes up the radios.
So now you’ve packaged the problem in a new layer that doesn’t solve anything but creates new problems.
The concept of an open connection waiting for the server to say anything is not novel or special, it just, as we already know, doesn’t really work reliably, you have to do more work to make it reliable.