I would add that Bluetooth Low Energy isn't totally free. Somewhere in your cost you have FCC/IC/CE testing, Bluetooth licensing/testing/certification, possible software stack cost and more expensive components (radio, antenna, etc). You also have a larger power requirement as low energy isn't as low as UART. I won't give specific numbers here as I cant't legally, but the cost difference is probably a wash. That's assuming your doing the radio layout and not using a module. Apple's move to wireless is definitely for their sake. I could also see an argument made that because of the possible extra costs for doing Blouetooth Low Energy (chips, testing, power, RF design, etc) you may see less accessories for a while.

In any case I think you're right that the tell tale signs are there.