Individual machines within the datacenter may be getting hit. But those machines are (should be) isolated from each other (or from other orgs).
So imagine company A has a cabinet full of machines. The fact that company B has a cabinet full of machines in the same building doesn't make it more likely that it gets infected.
So imagine company A has a cabinet full of machines. The fact that company B has a cabinet full of machines in the same building doesn't make it more likely that it gets infected.