I agree that there is probably a limited market for preinstalled Linux. Perhaps it's an option for folks who want/need Linux and don't want to deal with any of the complications that often exist for desktop use. I figure part of the allure is also that the machine is then inherently optimally compatible with Linux to begin with. I'm not sure how much that matters in practice these days though since there seems to be very few commonly used components that have poor support.
I'm buying laptops with preinstalled Linux and then I purge it and install Arch Linux on it. But then I'm at least sure that there are drivers for all of the hardware build in there somewhere and I can install them and use everything build in. Also I'm hoping to vote for Linux support with my (or my employers) wallet.
True, I suppose some mismatched or buggy hardware is a bigger issue in laptops. Like it's a pretty big problem if the wifi driver on my laptop is buggy in Linux, though nowadays that likely means it's buggy in Windows anyway.
The last laptop I purchased would literally BSOD only when connected to certain manufacturer (Cisco) access points under unclear conditions. It was a known bug. HP never bothered to release an installable patch and the one provided by Intel made the computer unbootable.
But I suppose there's likely still a market for people buying enough computers at a time that the risk of a hardware issue is not worth the premium.