I have replicated the performance differentials (for Azure), and they definitely suck.

But people are REALLY REALLY expensive (not only the ongoing costs, but hiring, firing and overhead), and Cloud has another huge advantage: accounting tricks (which help a lot to said midsize firms).

Literally one of the first things they teach you at the Azure training is the difference between CapEx and OpEx: https://docs.microsoft.com/en-us/learn/paths/azure-fundament...