And for anyone saying that QNX has drivers for whatever processor and should be compatible with BB10, think again. Let's use the AMD radeon drivers for linux as an example:
Linux Download Center
So even if different linux distributions have similar kernels, the drivers are still separated by distributions. The same difference could exist between pure QNX and whatever changes were made to it for BB10. There is also a separation between 32bit and 64bit versions for older driver version. BB10 is 32bit, but as far as i know, QNX moved to 64bit architecture.
Those QNX drivers may be a starting point for some drivers, but make no mistake it is not an easy task. It's a time consuming job to validate drivers and every bug found and change made requires retesting everything.