This is the battle cry that started the Open Container Initiative. But in reality, are/was multi-cloud and vendor lock-in true concerns for software teams? Tyler Treat writes on his personal blog:

We want to be cloud-agnostic. We need to avoid vendor lock-in. We want to be able to shift workloads seamlessly between cloud providers. Let me say it again: multi-cloud is a trap. Outside of appeasing a few major retailers who might not be too keen on stuff running in Amazon data centers, I can think of few reasons why multi-cloud should be a priority for organizations of any scale.