AT&T Wants Device Subsidies to Be As Low As Possible

I like the idea and think it would work. However, would the carriers reduce their charges if they no longer subsidized the devices? Since there is a portion of subsidy payback rolled into the monthly service charges, as evidenced by the prorated ETF's, would the mothly bills decrease, or stay the same? If there is a "rental"fee on the monthly bill, would there be an ETF or would the device have to be returned if you cancelled early? Or would you see no upfront costs for the devices, but an increase in the monthly bills for the rental fee with no reduction in the current monthly service charges?