From the article:

The strategic benefit of open sourcing software like TensorFlow or Kubernetes is that it allows Google to influence industry direction. The same is true for projects Google didn’t start but actively contributes to. Take a stroll through the Cloud Native Computing Foundation’s Devstats pages and you’ll find Google is a significant (if not the biggest) contributor to projects such as Envoy, etcd, Knative, Istio, and more.

Maybe the thinking behind the layoffs is that, now that open source contribution has become standard operating procedure at Google, there’s little ongoing need for the influence of Googlers like DiBona. But this ignores the fact that he and the others who were let go have done the behind-the-scenes architecting, strategizing, lobbying, and executing to make open source essential to how Google functions today. You don’t lay off that much experience without repercussions.