I believe the "d" part of "dGPU" is tripping you up here -- the "d" is "discrete", meaning unbundled from the CPU. IOW, Intel GPUs that are not bundled with the CPU have roughly a 0% market share.

Source states "Intel GPUs are not supported", parent comment noted Intel discrete GPUs have no marketshare.

Parent comment is thus irrelevant at best, misguided at worst. Not supporting Intel GPUs is throwing away the dominant leader in the GPU market.

We're talking about a dedicated gaming system here, iGPUs are pretty much irrelevant in that context. Things would be different in the context of a browser or word processor.

Besides, counting "1 Intel CPU sale = 1 Intel GPU" is misguided since that would count everyone using an Intel CPU with a dGPU as an Intel GPU customer, even if the iGPU sits idle 100% of the time.

Looking at a more representative demographic, the Steam users[0], Intel has a 9% market share, vs AMD's 15% and Nvidia's 85%. I don't know whether this also overcounts hybrid-GPU users (Optimus/DSG) into the iGPU bucket as well.

[0]: https://store.steampowered.com/hwsurvey