Sorry, Chris, but I'm not wrong. Surface tension = cohesion. They say lower adhesion, I say raise surface tension, these are two ways of saying the same thing.
In that article they talk about wax filling in the imperfections of the paint (making the surface smoother, and a smoother surface has less surface area to present). A smooth surface always has a higher surface tension than a rough one. Was I technically wrong by saying that the PAINT is beading the water rather than the microscopic layer of chemicals that are making the surface smoother? Perhaps....wow, ya got me there
They also talk about wax being hydrophobic. This was true many years ago when car wax actually WAS wax, or at least had wax/parafin in it. Those products went the way of the Dodo a while back because that stuff built up over time and clouded finishes. We still call it car wax, but these days there are much more advanced chemicals in use, but they all pretty much do the same thing - they polish down and/or fill in surface imperfections in the paint to raise the surface tension (by lowering the surface area), which blocks out contaminants (like water)
Water Wetter lowers the cohesion, that's what a surfactant DOES, by definition.
Go back to school and try again. Or at least find an article that wasn't written over decade ago.