At first I thought this was one of those whinges that don't have much merit, but then when I thought about it, perhaps not. Of course, I wouldn't dream of setting foot on a plane without my ipad and a book (in case the ipad wasn't allowed at points during the flight). I will use the IFE if there's something on it that takes my fancy, if not, I go the ipad. BUT imagine if I didn't own one and got on a plane expecting IFE and found none, I guess I'd be pretty narked.
I wonder if it's not unreasonable for the airline to advise pax at online checkin what's going to be available so they can make plans? Obvs, equipment can change, but most of the time, it wouldn't, and this might help some people.
To the OP though, I'd echo the suggestion above of becoming more self-sufficient with on-board entertainment. It wasn't so long ago that drop-down screens were the only thing you could hope for and no-one complained back then.