So what?

It makes sense.... You don't see DAL starting a JFK-CPH on a 777 do you?
It started with a 757 (RJ of the Atlantic).

DAL pilots should be happy that the company isn't over-committing resources in an effort that would end up causing a loss and losing money!

DAL pilots should be sad that they (and the other majors) have not forced the issue to return the block hours for DAL pilots to fly.

It's NOT the business of a pilot union to determine the aircraft a company uses on a route, it's the business of a pilot union to make sure that the aircraft is operated by it's members, under the best working conditions possible.