There's an airline industry for the simple reason: Cabotage.
There would be no US airline industry otherwise.
So you are saying that the US airline industry is the only unionised airline industry in the world?
Or are you trying to suggest that things would be so much better if only the plucky Nigerian and Venezuelan aviation industries were given fair access to the lucrative NY-LA route?
Or are you conceding that there isn't, in fact, any "devastating" going on at all, but that if everything was totally different, there might be?
OMG!!1! We must act now, to prevent the airlines being devastated by massive changes to their operating environment, involving alterations to long-standing international treaties, that nobody is calling for! Those damn, damn, unions. It must be them at the root of this non-issue.
Meanwhile back in the real world, pilots with long experience are retained by airlines, who pay them well because they recognize their value, not just as pilots, but as trainers and mentors to their more junior colleagues. Obviously the fact that the unions do not object to this practice imakes it bad. It is only good when it is done to a greater degree to retain much less skilled executives; in that case, it is fine, because the executives don't have a union. It makes me wonder how executives can get such good perks and pay, with no union to give them a voice in the boardroom. Oh, wait...