> Maintaining infrastructure on 3 cloud providers that don’t work the same is costly.Maintaining the ability to move between providers is not at all the same as maintaining your systems on all three simultaneously.
> All of these services provide pretty steep discounts (as a percentage of original costs) for customers who are able to [...] make long term commitments.
Sure. But the question is, at the end of that commitment, are you locked in to that provider by the cost of having to redevelop for a different provider (which gives your existing provider an unearned pricing advantage), or can you switch providers because you had the foresight to make sure your deployments were portable?
> most cloud customers would spend more money hiring additional engineers to maintain more complicated infrastructure then they would save trying to take advantage of this trend.
Sure, because most cloud customers are small and are drawn by the prospect of not maintaining infrastructure at all (in other words, they're actually SaaS customers by preference), and the non-portability of G-Suite's integration with GCP as compared with Office 365's integration with Azure is relatively immarterial compared to the non-portability between G-Suite and Office 365.
But (right now, at least) at the scale where you are for example selecting a cloud orchestration solution, going for the one that provides better portability between different providers with an abstraction layer doesn't really impose additional costs (because you'll need to develop internal expertise in whatever solution you choose).