Do you have any specific APIs or features in mind?
I think most app devs look at the installed base numbers and choose to support 2.1+ or 2.2+. I can't think of any APIs in 2.3 or 3.0 (or even 4.0) that are so wonderful that they are worth cutting off such a large part of the potential customer base.
From talking to senior flight attendants about how things used to be in the old days, I think the blogger is correct that strong unions are the reason for this change in the composition of the flight attendant work force.
As to why you see younger attendants on short flights, that's because long flights are more desirable for senior flight attendants. The way the flight bidding system works, a senior fa can fulfill their monthly flying hours quota by working 8 days of trans-Pacific flights at the start or end of a month, leaving the rest of the month free.
(a code review tool used by Android.)