Driver compatibility could be hell in windows as well if you're cursed with a "switchable" graphics option. My last lenovo could switch between on-board and dedicated graphics, but the latest video driver that lenovo provided was from the year before I even bought the laptop. If I used the card manufacturer's drivers, they'd usually work but killed the ability to switch to on-board graphics; but if I used Lenovo's drivers, games performed very badly due to how out of date they were.

Having one manufacturer and fewer models usually means longer and more consistent product support.