I guess this has been said before but I want to reiterate it here.
The 3 button navigation is simpler, much faster than gestures and less prone to input errors than gessure navigation.
It’s easier to use the phone one handed when using 3 buttons especially considering the size of phones nowadays.
The only real downside to the 3 button bar is the space it takes away from the screen. I can’t deny you get better immersion due increased screen size and gestures being intuitive (for me at least.
With that said I understand that depending on the brand the feel of gestures and their quality can vary (like between a pixel phone and a xiaomi device), but in terms of efficiency (and maybe slightly improved battery life due to less animations) and simplicity the 3 button navigation is still miles ahead.
I prefer gestures, it feels more natural and there is a bigger margin for error, as in I can swipe from anywhere along the bottom to go home or anywhere along the sides to go back. The one downside for me is the left back gesture conflicting with drawer navigation, but apps seem to be moving away from that anyway
It is also sometimes annoying when you try to crop the margin of a photo and the cropping area overlaps with the back gesture trigger area. But for me gestures win every time because the back gesture, which is the most common of the 3 operations, is available anywhere my thumb currently is, not just on the bottom edge of the screen.
Pro tip, press left edge amd hold for 0.5 seconds then swipe right. Works every time