"is particularly concerned that a ban on non-vendor firmware will leave stranded users with orphan devices that no longer get manufacturer support."
BULLSHIT!
There are billions of devices in the wild which no longer have vendor support. Apple's recent iOS9 left older models out of support, and Android in its various guises could be viewed as worse given there are many smaller vendors who customise the OS with their own mods and orphan models more regularly.
Or are the FCC going to force all vendors of radio equipment to support for life?