> In-house development teams have more agility in standing up new services, since they can just use EC2/ECS/one of the other 1500 container runtimes AWS has, rather than having to wait for someone to provision new physical servers for them.

How many people run physical servers 'raw' anymore? I would hazard their current stack involves VMware, Hyper-V, Open Stack, or a combination of the three.

You can have an API system spin-up just as effectively in a private cloud as a public one.