This is is in many respects a successor to a blog post I wrote last year about what I want from software infrastructure, but the ideas morphed in my head into something sort of wider.
Here's a theory I have about cloud vendors (AWS, Azure, GCP):
Cloud vendors1 will increasingly focus on the lowest layers in the stack: basically leasing capacity in their data centers through an API. Other pure-software providers will build all the stuff on top of it.