On the issue of being dropped, for me there were 2 reasons I've been dropped:

One was in a 4/5 crit - my first crit after a crash in a cat 5 crit. I was dropped in 3 laps. Lack of confidence was the definite issue there. For confidence, you really need pack experience.

But the other reason is lack of repeatable top end power - you don't get that unless you are racing or doing some serious interval work. But that can be built relatively quickly. We have a local Saturday fast group ride. I was dropped twice the first time, once the second time, and after that I was helping reel in breaks and contesting sprints. It took me all of 2 weeks to build the fitness needed. Granted, that was after I had at least a bit of base fitness, but there's gotta be some way to let all cat 5s everywhere know they won't keep getting dropped forever!