Actually I don't see a real roadblock here regarding FSF's position.

You should easily be able to arrange the device so that there's no firmware provided by default, so that it is up to the user to download and flash the CMT firmware if she so requires.

Without the non-free FW, the device should still operate as a nice handheld computing platform and if included/expanded with the passive receiver mr. Stallman proposes it would still be very useful device.