I don't know how anyone could expect anything other than what has happened.
In 1995 the Pentagon decided to bet the entire future of air power, for the US and its allies, on a single, fixed set of RCS numbers (magnitude, aspect and wavelength) and an aircraft that was in other respects no better than what it was replacing.
It will have taken 25 years by the time that solution is in service in significant numbers, and it will take 30-35 years before those aircraft are the majority of the fleet.
Surprise, surprise - adversaries use that time to react.