Web workloads aren't super CPU intensive on their own. You take some bytes from the network, parse them, make some calls to services on an internal network, th

Web workloads aren't super CPU intensive on their own. You take some bytes from the network, parse them, make some calls to services on an internal network, then serialize and send network bytes. Most of that workload is waiting for the network bytes to come and go. For that kind of work it's all about power efficiency and Amazon is able to specifically design their gravitons to have just enough cache, CPU speed, management components, etc. to get the job done and nothing more. A bog standard Intel CPU is designed for any and every workload so it's going to be idling and wasting power on components and transistors you never use or care about.