Airplay works through your local WiFi network, so if you turn off WiFi on your speakers and they are not hardwired to your router, they cannot work with Airplay.

If you turn off the radio (‘WiFi’) on any speaker that’s not hardwired it won’t work at all, never mind Airplay, as it would be disconnected from the network.

I think the OP was asking about whether Airplay would still work to a Sonos unit which was wired, even if its radio was disabled.

The answer is YES. Airplay is a higher layer protocol, running over IP, which runs over any layer 2 technology: WiFi, SonosNet, Ethernet, etc. so it doesn’t matter how the Sonos device connects to the network. 

@ratty That was exactly what I was asking about. If a hard-wired device, with wifi turned off, would still have Airplay function. You answered that for me. Thank you!