> There's some sort of folk wisdom that the lowest layer of cloud services is a pure commodity service.
> Cloud vendors might be pretty happy making money just in the lowest layer. Margins aren't so bad and vendor lock-in is still pretty high.
It may be folk wisdom, but big customers look at stuff like storage and CPU pricing when picking a vendor, because they need lots of storage and CPU. These services, in turn, are priced close to the actual cost of the underlying storage and CPU because of the high volume of storage and CPU involved.
I have worked at cloud vendors. Margins aren't great. Cloud vendors are always asking questions like, "How does vendor X sell this for so cheap? We can't make a profit at that price! How can we make our costs for X lower?" The lock-in is seen as a way to sell the higher-level services.
However, the high-level services, the stuff that start-ups compete with, also face competition with open-source projects. Things that used to be SaaS are now DIY with open-source projects running on IaaS. Ten years ago you had no Kubernetes, and you didn't have columnar storage out of the box on PostgreSQL. Cassandra was immature. Nowadays, open-source software running on IaaS has killed the need for bigger segments of the SaaS market, assuming you have enough expertise in-house to run it.