I think it mainly works for startups which can build it as a greenfield and are extremely sensitive to scaling (either they are exploding within 2 years or they're dead within 2 years). So they plan to scale from 0 to millions quickly. For that kinda business it makes sense because once the exploding growth comes it's super easy to scale up and even do that automatically. That's the power of Kubernetes.

For an existing business not in a hyper-growth phase with lots of restrictions and policies and processes and legacy stuff it's just extra work with no gain. It's just a round peg in a square hole. Wrong tool for the job.