No, you still didn't answer the question. It seems like you wanted to imply your answer is no, there is no limit on how much concentration of wealth is ok, by adding a lame qualifier to try to have it both ways, 'as long as other groups are capable of gaining wealth'.
Clue: as inequality gets higher and higher and higher, other groups are less and less able to gain wealth. If they weren't, wealth wouldn't be so concentrated. That's one of the effects of very high concentration of wealth.
You're being rather pointless to talk to. It's as if I asked you about slavery being wrong, and you would only answer, 'well as long as the slave continues to have their freedom, slavery is ok'.
And this is part of the discussion to try to help you get a clue - to understand that your ideology worshiping unlimited concentration of wealth has problems you don't understand. That a big part of what happens with high concentration of wealth is that the wealth
is use to protect the fortunes of the few who have it - by definition they see 'others capable of gaining wealth' as a threat to themselves. They're against that opportunity.
Ask your local cable internet company how much they will encourage others to compete in the cable internet market with them, benefiting consumers but slashing their prices.
I've heard that in England, you might have 50 choices for service. The result is that it costs a lot less for a lot better service. Net Neutrality would be less of an issue because someone could offer it for competitive advantage. But in the US, thanks to right-wingers like you, we don't need that - one provider in a market is great, and their exploiting their monopoly by lobbying for and getting the right to make billions by selling access - great!
An effect of very high concentrations of wealth is that anything that makes money - like big companies - simply gets bid up more and more in value by the few who have more and more, making it harder for anyone else to own a company; funds dry up for entrepreneurs and others to get that chance to make money and innovate, and offer competition. Productivity falls, the economy grows less than would and might shrink eventually.
Any rational person doesn't see that as a good thing, unless they're a sociopath who is one of those few and wants plutocracy. But it doesn't get a lot more evil short of genocide - it's anti-democracy and hugely harmful to most.
Of course it starts in smaller amount - as we've seen for decades in the US, income for the bottom 80% has been flat while all the economic growth has gone to the top, instead of a rising tide lifting all boats. That's what you want.
And that results in the opposite of democracy, the rule of the people - it results in the rule of the dollar, buying public opinion and elections. Which is why we see their hired help controlling all the branches today, and their taking yet another $5 trillion.
So, no, you have not answered the question.
Now I've given you a lot to think about. But I'm going to give you one more thing.
You talk about 'if upper increases its wealth by 20% and the middle class by 10%'. This again shows the ignorance from your ideology. We could talk about that hypothetical, but it has nothing to do with the facts. For decades, it hasn't been 20% and 10%. And you simply don't understand how even if it were, the ongoing 20% and 10% always will result in that 10% ending. That that is the very nature of income inequality you are ignorant of because of ideology.
In fact, for decades, the real income of the large majority of Americans has been not 10% but 0% (if not worse), and the upper groups have taken all that growth, up over 100% over time.
Look at this chart and pay attention:
https://www.financialsamurai.com/wp-content/uploads/2012/09/income-inequality.png
One last thing - what do people think the amount of equality should be? What do they think it is? And how does that compare to the facts? One more chart for you to look at:
http://static3.businessinsider.com/...ably-small-portion-of-the-countrys-wealth.jpg
Think about over half the country in that tiny bit of wealth on the chart. That's your 'able to gain wealth'.
If you are starting to get some clue about the idea - it'll take you time to start to realize how wrong your ideology is - great. If not, you seem hopeless at this time.
And you did not answer the question. You don't get to ask questions until you show you are listening - otherwise it's simply changing the subject, and that's not what I'm interested in.