BDAttitude
So if the aircraft had ACARS, and the Belarus ATC would have passed the same information about threat to aircraft via OCC, what would have changed then? Should the airline just ignore the threat message, because they can't trust the ATC of the country which their aircraft is currently overflying?
The solution here isn't in ACARS, it's in stop flying to/from and over countries where ATC is complicit in endagering aircraf - which is what has happened.