This is your opinion. The opinion of informed observers who are actually doing the work is the opposite - OEMs produce buggy, incomplete drivers and don't care to fix the bugs. In fact, given the choice, they don't want to allow anyone else to dig into their drivers because doing so can only lead to embarrassment. Plus exploits that are discovered are likely to be cross-platform exploits.

Any operating system that wishes stability therefore has to put barriers between themselves and the driver. And, preferably, should use drivers that they can audit themselves rather than trusting OEMs.

As an example of this outside of the open source world, the biggest reason why Windows used to have a reputation for BSODs is that they were dependent on third party drivers. Windows made it harder for third parties to take down their OS, shipped tools to audit drivers for bugs, and forced OEMs to clean up their act. (Which they didn't do voluntarily.)