It seems like the issue isn't overall seniority over the long run, it's the initial assignment that could take some time to move out of if it's not a good match. That kind of thing is simply harder on people with less years remaining.
Sympathy for that kind of issue is hard to find, everyone goes through new guy issues and getting a plane and/or base at the bottom of your list is sometimes part of the deal. Seems like some companies throw the old guys a gimme at hiring time 'cause they have fewer years to make up for it, and some companies don't.