There's so much hardware and software churn these days that the driver availability argument probably isn't as important as it once was. So much stuff is probably being done for individual products that people are undoubtedly having to write code for new hardware, anyway.
Sure, but is that a result of the hardware actually being that different or is it just because manufacturers aren't actually upstreaming their code? In the latter case, everyone would have to keep rewriting driver code, but not because it doesn't already exist - just because they can't cooperate.