I haven't had cable for years.  I "airplay" a lot from my phone to my TV.  This is not going to end well.  In the last 6 months to a year  airplay doesn't work very well.

My question is this...

1. If you can play music from your phone/tablet directly to Sonos
2. Link your iTunes account directly to Sonos.
3. Stream Apple Music directly from Sonos.

Then what exactly is the point of Airplay?

Sounds like you'd be jumping on a horse to go to the store, when you have a better faster vehicle to get you there.