https://www.idc.com/getdoc.jsp?containerId=prUS47529021 says the server market is about 12 million servers in 2021. I don’t think you can call that “economy of scale”, compared to 200 million iPhones.

(I’m not sure whether that includes servers at large cloud providers, but I don’t think that matters. Unless there’s a huge performance advantage, I don’t see Amazon, Google or Microsoft buying Apple server CPUs)