Ganna was in the same situation, but paced his effort better and, at his weight, surely is in fine form. It will be interesting to see how he goes in the classics and Giro (for the TTs).Alto del Colorado is the weirdest climb of the year:
First race of the season for almost all european riders
Riding on austral summer, as opposed to the winter season in Europe with little time for adaptation.
Shallow climb, more of a constant uphill drag rather than a proper climb except for a couple of kms.
Extremely high altitude (similar to Stelvio) and very exposed to wind.
In proper conditions, it's true Evenepoel should fancy this climb, but taking everything into account, I wouldn't read too much about this performance.