There's a process, a technology, a science that has to be applied to shape and command natural forces. Human psychology is no exception. Things must be done within workable, realistic parameters. We can't just say "everyone will share and be happy and nice now" and expect it to work like that.
"Corporations as people" is a massive politically-charged misnomer that doesn't mean anything by itself. The entire point of incorporation is to create a separate, independent legal entity divorced from its principals. This is what is meant when "legal personhood" is discussed. You have to be specific about what you'd like changed.
There are rules and laws, like taxes and regulations. These are meant to effect the underlying economy; they are not the underlying economy itself. The economy naturally emerges as people make trades based on what they believe their local optima.
We can (and probably should) do things to try to change peoples' perceptions of their local optima to better align with what we believe to better approximate global optima, but people won't simply accept the dictation of a new optimum if it doesn't align or compute internally. It has to make sense to them or they won't make the trades we want to incentivize.
The tax code is such a complex disaster for precisely this reason. It's the most direct way the government has to bias or influence the economy toward certain trades and away from others, so they adjust the tax system to try to affect the calculation of one's local optimum for a given trade.
The debate over which rules, regulations, incentives, and disincentives work best, as well as the holistic systemic approaches that tend to result in the best overall outcomes, is an entire field of academic study called "economics".
Economies cannot be trivially changed by fiat any more than the weather can. Yes, we have governmental standards around meteorology, but making a law that all thermometers must now read 74 degrees F does not magically modify the underlying system. It does not change the actual factors that occurring in the physical world. It just creates a credibility-destroying facade.
The same is true in economics. Pretending otherwise is simple naivete.
The extent to which "natural" inequality is amplified by institutions varies. Dictatorship is a very "natural" way to distribute rewards.
We don't have to accept dictatorship as our destiny just because it is "natural", nor do we have to accept current levels of economic inequality as immutable.
Second, I'm not saying that we should treat economic inequality as something that's static or immutable any more than any other natural force. I'm saying that we have to recognize that natural forces dictate behavior and economics, and that you can't change natural forces by decree alone (e.g., passing a law that says "everyone now must share"). We have to really appreciate and understand the processes and motivations that drive the behaviors if we want to address them in a meaningful way.
We have to be honest about how changeable certain things are. For example, we have not, as yet, found a way to control the weather explicitly, but we have coping mechanisms like air conditioning that mitigate some of the negative effects. This didn't happen by saying "It shall always be 74 degrees indoors at all times" and then laying down stringent ideological enforcement to ensure that everyone accepted and believed that it was always 74 degrees. It happened by experimentation, tinkering, and respect for the constraints of the reality that allowed us to discover a non-ideal but workable solution that mostly handled the problem of uncomfortable heat.
There is not necessarily any reason to believe that the current mix of inequality conditions are particularly cruel or unfavorable. American free-market enterprise may not be perfect, and I'm not saying that there are no systemic issues or that things aren't worsening, but our economic system is historically workable and reasonably well-tuned. It has proven much better than many competing systems. We have to be honest about where we are and what's possible.
We can't simply change "the rules" and expect a good outcome, as the comment I replied to implied. There is no magic wand and no overnight perfection.