Can anyone elaborate on what a company wide restore operation looks like in a big company? I worry about this because IT support teams tend to test restores per

Can anyone elaborate on what a company wide restore operation looks like in a big company? I worry about this because IT support teams tend to test restores per system. But what if it's thousands of systems going down at the same time? If this happens I even wonder how long it would take to restore productivity if the ransom is being paid. Also, what percentage of systems would typically be infected?