If you're not aware, Intel has released a lineup of laptops, with some models having the GPU made by them and some having the same GPU made by TSMC. That makes the comparison very direct. TSMC can deliver nearly 3 times the power/performance.

GPU and CPU manufacturing is the same thing, same node, same result. GPU is always maximizing perf/power ratio because it's embarrassingly parallel, leaving no room to game the benchmark. CPU can be gamed by having a single fast core, that drops performance in half as soon as you use another core.