You are a little off. Not all of them are back in the "friendly skies". Yo-nited sold a high number of their 400's after 9/11. Thai Airways got a smoking deal a few of them. UAE got 2 of them as well.
Did I say ALL. Nope I said MOST and MOST are back. A few were sold but the majority of the 400 fleet was saved.
Back to the XJET issue. If you are a DOJET driver then you are probably ex ACA and can speak first hand of the results of OWN branded flying. That really worked out well for you now didn't it.