No but wasn't this issue was really obvious? like 4 digits number ending? could be a technology issue if this was invented in the 80's but as time progress the

No but wasn't this issue was really obvious? like 4 digits number ending? could be a technology issue if this was invented in the 80's but as time progress the engineers should have seen coming this. and why cant we just use the same set of numbers again? like a flight from toronto to brazil or any part of the world , the flight will always be the same, there will always be a set of people that would want to go brazil from toronto. it will be easier that way to find the flights online and people can even memorize.