Your all right to a point / close:
Here are the main factors in order of importance:
a. White paint is both cheap and easy to apply.
b. White paint on most of the aircraft allows for quick and easy resale (the new airline simply puts new tail art on it)
c. White paint shows any anomalies quickly - hydraulic/fuel leaks, dirt, damage.
d. White paint has the best thermal reflective properties for both radiation from the sun - and reflected radiation from the tarmac (although in northern climates / winter this is reversed)!
People don't generally choose their airline because of it livery - they generally choose the cheapest fair. therefor white paint is the colour of choice - It all boils down to money folks…. :)