The real winner in the Mac GPU lineup is Intel.
I remember back in the day when a key difference between the MacBook and the MacBook Pro was that the MacBook had integrated GPUs and the Pro had a dedicated GPUs. Not any more. Now there are "Pro" computers with Intel integrated video.
But, Intel's Iris line of integrated GPUs are quite competitive to the low power discrete GPUs that go in the macbook pros. For example the AMD M370X is not even twice as fast as the Iris Pro Graphics currently included in the macbook pro.