I think the current system provides phone access capability as needed. CO has Verizon inflight phones - and if you have a Verizon cell phone you can setup to make and receive phone calls with billing to your cell phone bill. Pricing is not that bad (not the $3.99 per minute + $3.99 connect fee).

Verizon pricing:

1. $.69 per minute (no connect fee) for incoming or outgoing calls (same as Verizon roaming).

2. $.10 per minute (no connect fee) if you subscribe to a $10 / month fee. Mainly for very frequent travelers and talkers.

Cheap enough, but still high enough to limit unnecessary calls. On a CO flight, I always key in my cell phone number and pin at the start of the flight. If you get an incoming call, you accept by entering your pin.