Paul 2412,
In response to your query, it's called tombstone safety.
Tombstone satefy means that although the manufacturers, airlines and regulatory agencies know it is unsafe, (usually because us pilots have told them) it costs to much money to change that system, until there is a fatal accident that forces the change!
Hence, examples like the continued use of HF in remote areas( while the pax in the back enjoy Satcom phones and internet inflight), last time I came out of Sao Paulo into the Atlantic, we did not have HF contact with Atlantico radio for over 2 hours ( they didn't have their CPDLC turned on that night!) , and all comms were Acars thou our operations for relay to them, including wx deviations.
Cost is now the main driver of safety in the modern aviation world, and will only get worse in the future!