Currently the most powerful AMD iGPU is Radeon 780M (found 7840U/HS and 8700G CPUs). Judging by Notebookcheck‘s results, M2 Max GPU has up 2× the fps in Borderlands, 2.5× the fps in Witcher 3, and 3× the fps in Shadow of The Tomb Raider.
As for the benchmarks, the M2 Max GPU has 4–6× the fps in GFXBench, compared to Radeon 780M. And the RDNA3-based 780M has twice the raw compute performance, compared to Steam Deck’s RDNA2 GPU.
Unfortunately, GPUs in handhelds are always severely underpowered.
M2 Max isn't available on the free market (as part) but if it where it likely alone would cost noticable more then what a full handheld can afford to cost
I wish Asahi would move forward much faster and I could game on it, but at this point, gaming on a Mac isn't really a thing.
Source: I have one from work that I really want to be able to play. Whisky, Crossover, Parallels, I tried them all.
With a caveat: at its native 1280×800 resolution.
Or those who play on recent handhelds. Steamdeck with integrated RDNA2 is very capable with even modern games. Sure, you can't crank it up to ultimate quality with hundreds of fps - but it's enough, and above the "cheap" level of performance.
Also, looking at geekbench results, it basically matches the M2 Max in a mbp.