Well, there are three predictable reasons for why this has happened, two of which you probably know and one you might not:
First, it’s more competitive now.
The higher you go the fewer the positions and the greater the number of hungry talented, people vying for them
Second, your environment’s more political.
People are jostling for power and stature and you’re just not a game-player. Even your boss is focused on his or her own career and is less inclined to spend precious political capital on you.
And Third .. (and this is the part you may not realize):
The stuff they used to reward you for – your Strengths – are now being held against you as Weaknesses.