Originally Posted by
DCAbaron
The difference now is the planes are getting older. The E-145s and CRJ-200s are now mostly 20-25 years old, they can’t have more than a few more years left in them. The CRJ-700/550 isn’t far behind.
In addition to this, United currently seems to be big believers in upgauging and providing dual class service. Of course an airline's business plans typically aren't worth the paper they're printed on, so my guess is that age ends up killing the 50 seaters before anything else.