I wonder how much of this is less about attraction and more about social skills. Granted, higher attraction affords more opportunity to develop those skills, but I have met plenty of charming people who were not conventionally attractive.
I think this is largely a distraction from the direct effect. For any level of social skill, good-looking people at that level are perceived much more positively than others at the same level.
The question of the causal effect between physical attractiveness and social skill is interesting, though. There are plausible stories both ways, imo: your version, and the contrary one saying that pretty people coast on their looks and the rest of us have to try harder to be interesting or appealing in other ways.
(It's also hard to fully separate the skills from the looks, because the same behaviours that work for a good-looking person might backfire terribly for someone at the other end of the scale. Do we say those two people are equally socially skilled, or the pretty person is more skilled because they chose a strategy that works in their context and the other person didn't?)
This was summed up well in the "Hello, Human Resources?" cartoon[1]
1: https://www.threads.com/@smiling__sisyphus/post/DN56r2hkRXs/...
The simplest explanation is often the right one.
Attractive people have advantage even without the social skills. We have all observed it. Don't cope.
But that's orthogonal to the question. It's probably true that Zuck's kids will do better than mine (though that also depends on how you measure things) but that doesn't change whether they'd do better if they looked better.