I don't think many look at wealth inequality in isolation, it's usually accompanied by how people are starving. E.g. "over 20 people die from malnutrition in the US but we have over 900 billionaire's" - e.g. each billionaire would probably only have to give $300k each (equiv to what the average tax payer gives to the defense budget each year) to prevent most deaths in the US due to lack of food - etc.

Agree. Focusing on the inequality bit feels closer to envy. But if the quality of life or something like inflation adjusted wealth is going up for everyone, or if it is above some acceptable minimum, then is it really a problem? Or just a reflection of how concentrated things can be in a technologically advanced world?

Agreed. Unfortunately humans are hardwired to compare themselves to others.