Some places are mandated by regulators to demonstrate multi-cloud capability as an extension of supplier diversity requirements. It can also provide greater leverage in contract negotiations, and more flexibility to take advantage of promotions and differentiated services if you are fluent in the belt-and-braces compute and networking.

Those caveats in mind, I largely agree with you. Many folks treat these incremental fees, redundancies and inefficiencies as a sacrifice made at the altar of availability without acknowledging that the ensuing complexity creates a risk all its own.