I think it's less about strict hardiness and more about suitability for mass growing in Washington. The Honey crisp has declined because it's getting grown in places it doesn't really do well. The Cosmic Crisp is bred for those very places.
So it may not be as good at peak (or it might, here in WA the peak of the Cosmic Crisp can be pretty high indeed) but it should stay strong over the years.
I encourage everyone to check out https://applerankings.com, I would describe it as Pitchfork for apple breeds.
Here’s their review of the Cosmic Crisp: https://applerankings.com/cosmic-crisp-apple-review/
Their top ranked apple is the SweeTango, and I agree with their assessment: https://applerankings.com/sweetango-apple-review/
Full ranking list: https://applerankings.com/pick-an-apple/
[1] https://en.wikipedia.org/wiki/Cosmic_Crisp