Air pressure is 1kg/cm^2 ... so you will need to make a hdd that can operate under 400 kg of external load. Getting to the point of vacuum is expensive too. And

Air pressure is 1kg/cm^2 ... so you will need to make a hdd that can operate under 400 kg of external load. Getting to the point of vacuum is expensive too. And hdd already require enormously precise manufacturing process.