They're probably just responding to demand. Preinsyallef Linux would only be appealing to newbies or people whose OS preferences happen to match what the laptop seller offers. Anyone who's been using Linux for a while likely doesn't think installing on a new laptop is a big deal and also has idiosyncratic preferences on how to do it.
(I, for instance, use NixOS, the market for which I'm sure will be miniscule for a long time yet.)