With linux options in embedded space aplenty, who would want to move to a propriety os? QNX's big brother Vxworks has already been pushed out of most consumer embedded devices and is now limited to space probes and critical medical equipment. I just don't see a future for QNX anywhere.
Not everything has to be linux. It's good to have options for avoiding monoculturalization.
For real-time systems, QNX should be compared to FreeRTOS, CMSIS/RTX, VxWorks, or, if you after the new cool stuff, Zephyr, perhaps, but not Linux.
There's BSD too (e.g. Playstation, Apple Airport, Some POS devices and printers)
Dealing with Linux can be a PITA. Once you get a base system up you still need to roll a bunch of our own stuff. Do you use System unit or systemd, etc. The driver api's are pretty unstable.
I make embedded linux device and I'm curious if QNX could make things easier, especially for long term stability.