Great article Patrick, and you touch on a lot of reasons why companies are moving to hybrid approach, for most it just makes sense.
What we are finding is that traditional steady state workloads encompass about 75% of the workloads out there which are expensive when running those in the public cloud. With these workloads, Public Cloud providers try to alleviate the cost burden with longer contractual obligations such as 3 years instead of a "pay what you use" model. More and more we are seeing customers that have gone "all-in" with cloud are pulling out due to the high cost of running these types of workloads.
The key is to provide a cloud like experience on prem for these types of workloads, with rapid deployment, fractional consumption with all the simplicity and rapid innovation that comes from Public Clouds but still provide the controls of running these workloads on prem, with SLA's, Governance and choice. It's a balance of owning vs renting, same idea when renting/leasing/owning a car or a home.
This is why software is eating the world in the IT Infrastructure space because it can bring these promises to Data Centers, much like Google, Facebook and other "web-scale" companies deliver.
Having said that, of course there are the other workloads that are elastic, unpredictable where the cloud fits very well, spinning resources up and down as needed whether that's a seasonal requirement such as an online retailer during the holidays..etc....or even a real/rapid change in resources, cloud makes a lot of sense.
The key, however, is building a single construct or Operating System in this model that stretches from edge to core to cloud, while providing all the above tenants but making it dead simple, while providing choice both on prem and cloud and making that experience seamless.