Except it's not the FAA or JAA's job to design & contract for those black boxes. It's Boeing and Airbus that have to do that. And yes, they do research a lot.
As you said, it's a matter of conservative tech more than cloudy Union protests.
Tech for DFDRs VDRs are supposed to still be working when almost everything else has failed. When engines, elec generators, hydrolics and pneumatics power have all failed, you don't have much left, and your sattelite uplink has very LOW priority among things that still need to be powered in emergency condition. Not to mention that uplink above the South Pole IS tricky.
Emergency conditions like that are supposed to happen somthing like 1 time every 10 or 100 million flight hours. What is the failure rate of sattelite uplinks ? of Sattelites ? what is the probablity of not beeing in sight of a sattelite ? what is the chance that the sattelite network you want to use won't be in use in 30 years when your plane finally needs it ?
Basically the recording systems have to be designed to that no matter the external conditions, it should work with the highest possible certainty. This pretty much rules out everything outside the aircraft
Why do you think GPS is still not the primary means of Navigation ? because it's UNSAFE. It's failure rate is not disclosed with enough certainty, it's reliance on government systems is unacceptable. (__foreign__ government, for 90% of the usefull world), the continuous maintenance of this network is not garanteed. It's exactly the same for Data Recorders. You just cannot trust the kind of technology enough for it to be the basis of your recording tools.
Airlines and governments are welcome to use any modern means of navigation, maintenance communication,... whatever, as __additionnal__ means of safety, but all this goes pretty much out of the window when serious problems arise aboard planes.