I get 3 tokens per second on M1 Max running 30B models compared to 1 token per second on a GPU (P40), both quantized to 4bit. So, in my opinion CPUs are better for inference (at least fast CPUs with DDR 5 versus cheapest GPUs).
The reason why GPUs seem to be the standard de facto is that they scale better, are more power efficient and are better supported by pytorch & co. Also, academia cares more about getting the best quality for their benchmarks, than about the performance and accessibility.