https://thenewstack.io/vmware-pivotals-pks-distribution-marr…
This article focuses more on VMWare but also indicates how and why VMWare and Pivotal are not competing against each other. Pivotal is for developers, VMWare for IT Admins. It also goes into some more technical details, mostly as related to VMWare, as to what PKS does, although at the end it talks a bit about the tri-Pivotal products for Kubernetes.
For those who like to be more technical, but not have to read the instructions or do the math.
Tinker