Companies shouldn't be creating towns, period. If we need new cities, their locations and forms should be chosen by the people. By elections. Not by some lone asshole whose only urban planning qualification is that he happens to have a large pile of money.

Man, so interesting. Why do we have to pay those workers to build something that society needs? Is it because the workers need to eat? Why are the workers starving? Is it because the food they need is locked away in a hoard of wealth that only gets distributed by people who own the hoard? Why won't they just feed people? Oh they only feed people if it means they'll make a profit?

Hmm. How does a system this cruel stick around? What's that? 90% of the wealth of the world is owned by a vanishingly small number of people who will only deign to feed people if it makes them a profit?

Man. Real "imperfection" you got there. I'm sure we can fix it with some reforms though once we learn more about economics...

15bn belonging to the genius

Oof.

Anyway...

The regulation part is absurdly easy: they get a tax bill, they sell their shares, they pay the tax bill.

Operating costs don't have anything to do with personal wealth. The company pays the operating costs. If the company's revenue is greater than its costs, it pays dividends or reinvests and in theory, the stock prices goes up. See above.

The problem isn't the logistics: point gun, take money. That's pretty straightforward. The problem is ramifications. If billionaires can no longer grow their wealth, what would happen? Well, for one their control over these companies would wane. If Musk can't own more than a billion, then he'd have to sell a bunch of stock, which means he would have less control over the board, and thus less control over decision-making. But is that such a bad thing? Are the skills and personality that cause a company to go from zero -> public the same ones you want once the company has grown to a large size? Idk, maybe ask Zuckerberg about Oculus Rift and the Metaverse.

I don't think anyone actually knows what would happen. But we do have a lot of data on what happens if you significantly increase the marginal tax rates for upper income brackets, and it sure seems to benefit society as a whole, but depends on what outcomes you're targeting. And that doesn't actually target the ~900 billionaires in the United States because most of them earn money through capital gains rather than regular income.

It is kinda done with a wealth ceiling if you tax the higher wealth more, but yeah let them make infinite money somehow if they are at the top end paying 99% of it back into society.

Suddenly the company is worth 25 billion, 15bn belonging to the genius, and the rest having 2.5bn stake.

This doesn't just happen. How did the value go up so much? Are their sales not taxed? Will the liquidation of this value not be taxed?

The core of literally any anti-billionaire economic policy needs to be the taxing of loans made on potential valuations. With that, the numbers you gave are effectively irrelevant because there's no more infinite money glitch. They have to liquidate assets to spend money, and must pay taxes on that.

If a company gets so big that it "needs" billions of dollars to build its own town then that company's profits and decisions should be split among its stakeholders (i.e. all of its employees).

If someone starts a company then they should be rewarded with profits if it succeeds. Contrary to capitalist arguments. The big brains behind companies don't do it to make 15 billion dollars. They do it instead to get obscenely rich, and despite our completely warped views with companies like Tesla and Amazon, "obscenely rich" starts in the hundreds of millions of dollars maybe a billion dollars if someone was an idiot.

On top of that there are thousands of examples throughout history that show that people don't invent things solely to make money and the original big brains behind company innovations were not necessarily profit motivated.