Compare for instance the Zen 3 upset vs the M1 upset. Zen 3 allowed the market to pick what they thought was the best CPU, the M1 allowed the market to pick if they wanted to buy an entire computer, OS, and software set because the CPU was good. Similarly with Graviton and Amazon, you can't just say Amazon is competing the same as Via, their interest is in selling the AWS ecosystem not in providing the best individual components. Same with Google and their custom chips and Microsoft with theirs now. Yes many are "just ARM" but due to custom extensions/chips and (in some cases) lack of standard ARM features that doesn't mean they are the same ARM.
Of course that's not to argue it's wrong because it's vertical integration, many will think that's the better way to make complicated products, but that's not the point - the way big companies are competing on chip design is very different than if one acted like an AMD/Intel/Via competitor to actually compete in the chip space instead of a larger space.
