The short answer is no.
Amplifiers (particularly valve amps) need to be used at least twice a year otherwise the electrolytic capacitors inside can dry out.
Think of it like driving a car. Cars don’t like to be garaged for extended periods, they need to be run.
Some of the worst sounding vintage amps are the ones which have been kept ‘showroom new’ and almost never played.
Some of the best sounding vintage amps are played regularly.
Also, speaker cones do not appreciate conditions of changing humidity. Pots also get corroded and go crackly.
The old adage is good: “If YOU wouldn’t sleep there, don’t store your kit there!”