Commissioned life versus active life for the Kirov class

Will the surviving Kirov-class nuclear cruisers outlast the Nimitz class because their large hulls allow modernization?

Possibly in years commissioned, but not necessarily in years actually operational or combat-effective.

The answer separates administrative service life from useful fleet availability. A ship can remain officially commissioned through a very long refit or periods of limited readiness, making the headline number misleading. The large hull and nuclear plant create modernization possibilities, but accumulated damage and the difficulty of completing refits still constrain what Russia can return to service. This is a useful warning against comparing warship longevity without also comparing active years and combat capability.