Wealth and consumption follow a power law. That's not broken.
Regardless of whether wealth should be concentrated like that, it still presents a significant problem for the games industry, and leads to things like loot box economies to milk the "whales" for thousands of dollars, since 90% of the addressable market can't afford the product.
The wealth inequality we see now is largely a function of every Republican administration in the last half century passing tax cuts for the wealthy while simultaneously dismantling unions and failing to enforce anti-trust, allowing market consolidation the likes of which we haven't seen since the gilded age.
The result is that wage growth completely disconnected from productivity growth to the extent that subsequent generations are now poorer than their parents' generations.
None of that happened naturally - it was the result of repeated policy changes by the government.
not to mention, the marginal propensity to consume for the top 10% is 5-6 times _less_ than the bottom 90%, so I don't know how you can claim the current consumption rate is good?
It's perfectly good for the economy if wealthy people save/invest in production instead of consume themselves.
Pointing out that poorer people have higher MPC simply doesn't mean that redistributive policies would increase production or consumption. It's entirely possible that such policies would decrease overall savings rate which you seem to think would be good, but would reduce total production and consumption.