I don't know to what extent you can disentangle cause and effect in human psychology. Certainly if you believe rich people are evil, you will feel justified in tearing them down, so you will tend to tear them down more, in which case it's a cause of the crab-bucket mentality. But you might also just feel a lot of envy for rich people and consequently engage in motivated reasoning that leads you to believe that they are evil, in which case it's an effect.
(Negative feedback systems in general do this weird interchange of cause and effect. An op-amp's inputs are kept at the same voltage because they're its inputs. It's a real mindfuck, in a good way.)
More generally, throughout history, most people who got rich did get that way by screwing over other people; I mean that's literally how warfare works, by harming the opposing forces enough to get them to submit, and in feudal systems (and quasi-feudal systems like the Argentine system) that's how you gain power and wealth. Feudal nobles and partisan politicians are whoever was historically best at harming the opposing forces. Most of human history isn't that, of course, because everyday life always works by cooperation and goodwill, but most of the parts of history that got written down were people competing to hurt each other.
The crab-bucket mentality is very helpful to politicians because it prevents upstart businesses (and regions, and cities) from creating alternative centers of power that could compete with the established order.
Capitalism was the decisive break with that tradition, in which people compete by doing the most good for their customers instead of harm to whoever their enemies are at the moment; but nothing in capitalism prevents powerful and rich people from hurting whoever they see as their opposition, except that it's unprofitable to spend too much on hurting them, and if you choose poorly they may be able to hurt you back, which is even more unprofitable. And whoever is powerful can use that power for harm, too, and being human, they usually do. Still, by changing the criterion for wealth from doing harm to doing good, capitalism changed the incentives enormously.