It seems like the only way into a major, at the moment, is to go to Piedmont and wait for flow through. I think that's the only AA regionalr airline that offers flow and E3.
For any majors or even any lcc's to seriously open the door to E3's, the aviation industry here would probably already be in a death roll.
The fact is that no amount of Australian and Irish could have any serious impact on the trajectory of the aviation industry, irrespective of which way it goes.
At the moment we are a band-aid solution to low wages in the regional industry, which I think is pretty evident, as Skywest stopped taking E3 new hires almost as soon as they put the pay up.