and your point is?
Which one of those went into production? Which one had fly by wire? Which one had a folding wing? Which one was designed for combat?
Both were R&D concepts and nothing more. Neither was FBW, which is no easy task (any idea how The S92F is coming? Rumour is it's been put on hold until the 60M and 53K are complete and the 2008 FAA cert date has come and gone.), and neither had anything in common with the V22 other than the concept.
From what you're saying we should see X2's darkening the skies in the next couple of years, since the original concept flew in 1973 there really shouldn't be much for them to develop, right?
Furthermore you do nothing to address the question. If it takes on average 10 years to upgrade, 18 years to develop a new model helicopter, is 25 years to develop something that's never been certified before out of line? If so why did the EH101 (just another helicopter) take 19 years (1981-2000) to get into service? What's up with the CH148? Heck, the civillians are already flying them so why another 9 years (or more) to get that into service with the Canadians? Why does the CH53K need 12 years to upgrade engines, install a glass cockpit, fly by wire and stick some new rotor blades on it? Why did they decide not to use the viscoelastic lag damper? It's just another damper right, can't be that hard?
I'll answer for you. Because development is hard, it's even harder when you're on new ground (V22 and X2). How long do you really think it will be until we see operational version of the X2? Will anyone be surprised if the CH53K doesn't deliver in 2015 but sometime later, considering it hasn't flown yet so it hasn't run into it's first development issue, of which there will be more than one.