making them practically unusable for open source OSes. even under windows they performed horribly. Good riddance.

From an open source perspective, there is hope with a preliminary reverse-engineering Mali driver recently merged into Mesa. Kernel bits aren't wired in yet, but progress has been pretty good recently. I wouldn't be so quick to say "good riddance" as a lot of very useful ARM boards like those from Odroid have a Mali GPU.

https://www.phoronix.com/scan.php?page=news_item&px=Panfrost...

I think this is a misunderstanding. I don't think Mali is available on a lot of windows devices. The parent was presumably talking about PowerVR.

There isn't a single igpu that's used on android phones that has mainline drivers. Pretty much all of them are practically unusable for open source OSes. The most notable exception is adreno which has a more mature reverse engineered driver. Now that their patents expired Qualcomm has contributed a tiny bit too. But other than that the rest still suck.

The Atoms with PowerVR were also put into netbooks, i.e. into a class of hardware, where you would want to install some Linux distribution.

Correct but that's still a rather small market compared to e.g. chromebooks which can use anything from arm or qualcomm.

Some Mediatek SoC still uses PowerVR.