"One is to avoid co-residency and instead use a separate, "air-gapped" computer for high-security tasks. " Seriously if you were doing "high-security" task why

"One is to avoid co-residency and instead use a separate, "air-gapped" computer for high-security tasks. " Seriously if you were doing "high-security" task why would you be doing them on a VM which allowed co-residency anyway?