Keeping systems isolated is an orthogonal concern. The question is weather rebooting the system is safer then shutting it off. The fact that shutting it off sho

Keeping systems isolated is an orthogonal concern. The question is weather rebooting the system is safer then shutting it off. The fact that shutting it off should be safe is a separate concern. At a minimum, shutting it off reduces your redudancy; and it the system fails again (even in an undetected way), that should be fine, because you (should) have enough redundancy to handle an arbitrary system fail in unexpected ways.