I'm not sure the comparison here. I could get 8 t3a.micros (16 cores total) for ~$700 reserved for 3 years, including power costs. And I don't have to maintain it, or the network connection etc.
But you do have to pay network usage by the gigabyte, right? And 8 full "hyperthreaded" cores in one machine are more useful than 16 machines with a core each, though I admit I don't know how much such a machine would cost on AWS.