Again, you've admitted your ignorance about the United States there, and the situation of hundreds of millions of people that live in it that are not functionally wealthy in a material way that they actually experience.

I am indeed ignorant about the United States. This may surprise you, but I don't know about every economy around the world. I'm sure you don't either.

But I do know that a capitalist system can work well without UBI, as proven by the German system.

(Yes, I will keep using the German system as an example.)

"the current system" is failing those people and no amount of being smug about how status quo poverty for people that scrub toilets and pick fruit is somehow a good thing will change that.

As long as we haven't fully automated it, people will have to scrub toilets and pick fruits in any econonic system. What you wish for is for them to not be poor. Which they aren't (in Germany).

ignoring that a tiny percentage of the population actually benefits from those riches and the rest experience staggeringly higher cost of living

Are you claiming that people's actual wealth has not gone up in the past 50 years? That we don't eat better regulated food, that we don't own very advanced devices, that we don't eat food shipped from across the world?

Normal people's wealth does keep growing. That is a very obvious fact. You may claim that it doesn't grow fast enough, but it does grow.