For what it's worth, after UA made their announcement of new seatback IFE coupled with streaming, BT compatibility, etc. I did make a point of asking internally if we would ever re-visit the IFE question, especially since it's clear DL uses that, in part, as a way to chase higher-yield customers.
The answer was an unequivocal, emphatic, NO. Not "You never know." Not, "Well, we'll see what the competition does." It was a flat, firm NO.