Ever since its appearance in Android Pie, I always consider 2 button navigation is a bad attempt by Google trying to play catch-up with the fad generated by the iPhone X. However, due to a bug with A13 QPR2 it had to be temporarily removed and many were not happy about this. So, 2 button navigation users, may I ask why do you prefer this method? To me it makes you do more for the same action whilst doesn’t save any screen space.
For Android power users like the people on this community, gestures are a no brainer. However for your average user they are undiscoverable and not easy to use. Especially for middle aged and older users.
Hence Samsung uses the 2/3 butto layout by default. My wife is 45 years old and can’t use gestures so she’s using the 3 buttons.
So is every other middle aged+ person I know.