Tbh I never read Gifted Kid™ Angst as “I’m no longer special” but more like “I had unrealistically high academic expectations put upon me at a very young age and learned to measure my worth by academic success and as a consequence constantly feel as if I’m not good enough”
Also we never had to study or try very hard in earlier grades, so by the time we get to high school or college, our skills have plateaued and we have no study skills to fall back on whatsoever. We go from excelling with no effort to failing and having no idea how to catch up.
Also, once you are out of school, there are no more academic tests with which to prove your own worth to yourself. This only heightens the sinking sensation of ‘I am not good enough.’