Well sure, the reduction of inequality is not a smart bet to take in the morally impoverished social climate that we live in. The original Pareto principle itself was born out of observations of the natural distribution of wealth among populations, so changes to that distribution will require active effort and hard work to create a sustainable economic structure. I'm not saying people don't have good reason to be cynical about improvements in the Gini coefficient across the world.
But you must recognize that human society is simply the summation of many individual choices, and there is a big difference between saying something is unlikely to happen, and something cannot happen. Pragmatism and cowardly cynicism are two different positions with dramatically different possible outcomes. Instead of accepting Keynes over Polanyi as a foregone conclusion, try looking at the individual choices that were made to get us to this position. Repealing Glass-Steagall in the '90s was a choice. Deregulation in the '80s was a choice. 100 million Americans eligible to register choosing not to vote out politicians who make these decisions are 100 million choices. There may be systemic reasons for why those choices were made, but I am simply right now trying to get you to see that these outcomes are not foregone conclusions.
Your justifying logic for holding your beliefs is certainly not rigorous -- you can just as easily find examples of nature favoring equilibrium and balance in every conceivable force diagram or cell membrane as you can of the existence of inequality. If you are looking for a nature metaphor, why not try a chemical reaction? In an inert environment, oxygen molecules will not spontaneously transform into carbon dioxide, even though carbon dioxide is a more stable chemical state. But once the necessary conditions exist -- the presence of sufficient carbon and enough available activation energy to perform the reaction -- a single spark can cause a chain reaction to convert every single oxygen molecule present into carbon dioxide molecule. No matter if previously, every oxygen molecule was insisting, "But this is the way things have always been for us! Some things can be changed, and some things can't."
We have not yet reached the necessary conditions for our society to reach a more stable state, so you are not wrong in saying that it seems unlikely that the reduction in inequality can occur without certain tipping points being reached. But it is folly to conclude "...there's not much that might change that" without educating yourself on the missing conditions and realizing that it is possible to slowly work towards achieving those conditions or empower others who are taking steps to achieve those conditions. Conditions like political will, corporate regulations and safeguards against regulatory capture, fighting disinformation campaigns, and educating people on the harms of inequality, done very well by thinkers like Stiglitz, Varoufakis, McChesney, Chibber, Polanyi, Bernie Sanders, John Kay, Tim Wu, and many others who have considered the effects and are working on solutions. So that when that single spark comes along -- a great leader who can move the masses to rally behind a vision of a better world -- hopefully we will have done enough to move in the correct direction. We are closer than we think probably, if you look at how close the elections of Gore and Sanders were, for example.
But, I should say in the end I am encouraged by anyone who is willing to read and educate themselves on the matter and engage with differing viewpoints. I wouldn't go so far as to say that I am optimistic for the future, but I will do whatever is in my power to create a fighting chance for those who have not yet given up in the face of difficult odds.