I could totally see this happen.

Not in a direct manner, but something about "OSM not living up to Apple's high standards of privacy" or similar strategy.

why would they do that when Google Maps and Waze are already bigger competitors?

If it's missing data (such as locations) that is the issue, then you can update the map yourself and help others migrate at the same time. Every little bit helps, even if you don't plan on fully moving over. I've done over a thousand changes to my local area and it's actually more accurate than Google Maps in a lot of the commercial areas. You don't have to do a thousand things though, like I said, every little bit helps.

Of course, it doesn't help for outside of your area if you only do changes locally, but if enough people were willing to update the map, things could change.