Well, virtually every major would have ceased to exist, and the entire scene would be dominated by what are now second level players.
Tom likes to spruke how good things are at Delta. Jet Blue, Spirit, Virgin America, and Trans Air (Before the SW takeover) pay NOTHING like what the legacy carriers do- and THEN there's what the US regionals pay!
BUT protected by their archaic Government protectionist bankruptcy laws, the Unions insist the Majors pay through the nose, knowing they can go broke on Friday, but will still be flying on Saturday.
Introduce a TRUE level playing field- even in the US Domestic market- and see who long Toms gravy train lasts!!