I do not think it will benefit the employees or american airlines.
Diesel
More like it will destroy the European Airline industry, despite US pilots earning way more than us we (in the UK particularly) are crippled by the high costs of regulation. In the cargo world we are already being overrun by UPS and others operating N reg aircraft with a lower cost base on intra EU routes. Add to that the threat from the East of ex soviet countries whose airlines stagger from one banning to another yet always seem to pop up with a new name and AOC elsewhere and we bear the brunt. And ont get me started on the Iclandics , pop 300,000 yet 50 large jet transport aircraft able to operate freely throughout the EU.
Things should change but not without reform of the european civil aviation administration and a level regulatory field for all.