Dessay was in her mid 30's when she recorded this in the comfort of a recording studio. She was in her vocal prime. Damrau is about 50 in this live performance, and vocally is not as fresh. I do get what you're saying: Dessay interpolates a brilliant high F sharp, while Damrau only goes up to an obviously not easy high C sharp, but comparing the two is perhaps slightly unfair. It must be challenging to find appropriate repertoire when you've established yourself as a coloratura soprano, but your upper range no longer extends to high E flat and those runs aren't as filigree as they used to be.
