^^ It is called an oligopoly: "a state of limited competition, in which a market is shared by a small number of producers or sellers."
I think this is hard to achieve and for sure not desirable. There is still plenty of supply from multiple 'producers', so there will be sellers and lenders for competing rates as well.
Plenty is the operative word here, when an entity has the ability to buy the marketcap without breaking a sweat then that "plenty" needs to be quantified and protected. And your idea of "plenty" is very far off the mark. Actually one of our Mathematicians should chime in to quantify what that number is.
Nobody can buy the market cap regardless of how much they have to spend because it is a moving target, and one that recedes faster the more you try to chase it. As long as some people refuse to sell even infinite money can't buy all of it.
The willingness of people to sell as the price goes up is natural and expected but also limited. Many people hold cryptos for moon and rising prices only increase resolve to hold (and for others to buy!)
Also, you still have to consider mining. As long as there is non-trivial mining that's another reason you can't buy the marketcap, because more coins are being added to it all the time. Anyone can mine even if "all" of the market-float coins are controlled by someone or by people who won't sell.
You are of course assuming that they purchase it quickly, they would not and there is no way to tell. I used Marketcap as a general number of worth, I'm fully aware its a moving target. :rolleyes:
Think about how you would do it and think about defending against that.
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Now it is great time to readjust the interest rates in lending markets. Looks like there are a lot of demand for Moneros right now for shorting purposes. Some kind of "OPEC" style of cartel could be formed in lending markets.

I agree that this needs to be done, but not for the same reasons. And not just for the lending markets but for the stability of the asset (and the dream). I believe it is inevitable that this coin will be attacked by TPTB and there is no way in which it can be defended against those without a significant portion of the coin being protected. It is just a matter of time and that time is running out as the false Anon coins fall like domino's. As a matter of fact I would not be surprised to find out that a significant portion of the asset is currently held by those powers right at this moment. Many discount my warnings throughout time and inevitable all my prediction come true. Discount this without preparation and you will suffer the consequences. I believe this is the most serious threat to this project, far and above any competitor whether current or future.
But I do not think You TrueCryptonaire are trustworthy enough to be part of this group as you will take the bribe when it appears with no thought to anything but your own self interest. But as for price fixing the lending rate I would say you would adhere to that partially just to make sure you make the highest returns possible. You are an exceptionally self centered person but at least that can be counted on. So I'm sure anyone entering in a deal with you will know that you will stab them in the back when it is to your self interest.
Where should we fix the minimum lending rates? I suggest between 0.075% and 0.1%. Defectors from our alliance only hurt themselves by getting dust instead of real Monero.
During a good rally, it's always fun the twisting the knife and inducing panic by taking all my available coins off the lending market for a while.

In other news, Dash is on life support. Expect their market cap to continue leaking into Monero, as Dash has no plans (nor ability) to defend itself against a Shen-on-Shadowcash style pwning.

If BTC wasn't on the rise I'd get back in to help you guys cut the shorters off at the balls.