Although I have thoughts on the matter, I'm not actually arguing about the quality of drivers, I'm arguing that x86 linux has had minimal problems with keeping all drivers in-tree, and if vendors want to support linux they've generally had no problem working with that. It is for some reason only mobile and embedded vendors that find it impossible to upstream drivers and that insist on shipping hacked-up vendor forks of ancient kernels.

And again, firmware is a separate matter; there's plenty of cases of linux shipping blobs for the device to run, so long as the driver to talk to that device is FOSS.