Success is mainly about sucking up to the right people. No matter how good you are at your job, you have to know how to play work politics. Most bosses don't know how to evaluate actual ability, and they're much less objective than they think. Usually they favor more likeable employees over capable ones if forced to choose. Human life is a popularity contest, always has been, always will be. That's the side effect of being a highly social species...
I don't think you're entirely wrong, but I think maybe you downplay the importance of a good team dynamic when choosing people. I'd take someone less skilled over a highly skilled but unapproachable jerk for the long-term health of the crew. In that way, I don't think it's bad to favor the more likable one depending on how we're defining likable, and I don't think that makes it simply a popularity contest either.