Hard to agree with those critics when the OS is doing the right thing, but the hardware won't play ball. The reason there's so much code in the Linux kernel is for various shenanigans that hardware vendors came up with. Yesterday I was looking at how HDMI audio is being implemented. From the specs, it looks quite nice with support for PCM and rates supported sent via EDID, but there's like 5 implementations for that one, 3 of them handling hacks by the GPU vendors.