[sarnowski]

A single software piece can't be PCI compliant but only how you use it.

You have to argue that Docker uses the Linux isolation mechanisms that make those containers virtual machines in the sense and spirit of PCI.

Treating containers as VMs makes some other requirements even easier like the request to have a minimal system and to only have one function per server - thats how you want containers to work anyway.

(Btw PCI has nothing to do with PII.)