Yeah it's small, but a few phones got burn in from it (my cousin's LG V30 is one example). Personally I use 3 button on a LCD screen so that's not a problem for me.
I felt the same. 3 button do the job quicker (a single tap to get what you want) but occupy a part of the screen. Gesture makes you do more but give you back the screen estate. 2 button seems to combine the downside without offering anything advantageous.
Love how Samsung still fight to keep a11 quick settings instead of bending to the new one