Cryonics itself makes no moral prescriptions. You can consider it as a type of burial ritual.
But rituals are not performed in isolation, they are performed in the context of religions (or religious-like ideologies, if you prefer) that do make moral prescriptions.
Cryonics typically comes in the transhumanist/singularitarian ideological package, which has a moral content.
Cryonics itself makes no moral prescriptions. You can consider it as a type of burial ritual.
But rituals are not performed in isolation, they are performed in the context of religions (or religious-like ideologies, if you prefer) that do make moral prescriptions.
Cryonics typically comes in the transhumanist/singularitarian ideological package, which has a moral content.