Am I just paranoid?
Don't be afraid my friend for now 930 and 1520 is the only devices to will take all features of windows 10
That's wrong. What if w10 for phones will include, lets say, that windows hello feature. I wanna see how 930 or 1520 will support it since they dont have IR front shooters. So no, there is little chance that every existing phone will support all features, but that in a good way. From the "inovation" perspective. Not from the "they didnt bother to optimize the new nfc system from w10 for older devices with nfc because it takes time, so only new devices launched with w10 will include it" thinking.
At the MWC 2015, Elop mentioned the Lumia 640 and 640Xl would get the 'full package' of Windows 10. Other than hardware restrictions, I can't why MS would leave the 940 out.
