IOKit predates anything resembling wide adoption of those C++ features. Exceptions are a particularly thorny subject when mixed with multithreading and (non-existent) memory model. And not to mention RTTI, which was always just a patch job.
I think choosing to exclude exceptions is a totally fine decision, and I actually think it's the right thing to do in embedded systems where you _cant't_ afford to let an uncaught exception bubble up
