Earlier quoted context omitted.
You don't have to be Netflix to get AWS, GCP and MS to play against each on pricing. I've seen a number of my clients build a prototype on each platforms, and then use it to make final decision. Part of that final decision is having the cloud vendors compete on price. I personally haven't seen any massive price breaks, but there definitely is room the margins.
Really playing these companies against each other would mean dynamically balancing your services across the providers based on pricing
It would also require an architecture that supports multiple interfaces. Totally doable (the facade pattern comes to mind) but you'd want to calculate the TCO to see it works out financially.