I have a similar issue but with the "IOHIDDeviceRegisterInputReportCallback". I've check
with an USB analyzer the packets are correctly transmitted to the mac but the callback
is never called. The same code work on all previous versions of macOS...
Did someone have any idea why ?
The SDL2 joystick library on Catalina crashes if you unplug a gamepad.
I just found that the system doesn't receive notification that the device has been used, and keeps using the handle, which causes a crash.
After some playing around, it seems that you can use IOHIDManagerRegisterDeviceRemovalCallback.
It is still working properly on macOS 10.15.