If you think so, you should explain where exactly the 1.624 trillions $ value of Google is, given that its net assets are about 267 billions $ and they had about 118 billions $ in cash (or cash equivalent)

You can sell a cow for $1000 on the meat market. Or you can keep that cow, so that it produces milk for many years and earns you a total of $5000. This is the difference between net asset value and valuation. If you were to buy a cow, and producing a cow was next to impossible (cows are one of a kind, like unicorns), then the price of the cow would be closer to the valuation than its net asset value. And once you have that cow, as a responsible farmer you will milk it to the last drop, to get the most out of your money.

Now I'm sorry for the cow, but a business isn't a living creature so exploiting it is ok.

The company isn't necessarily expected to grow. Companies are expected to be milked. Sometimes companies don't grow and that's ok, they're still being milked. The only requirement is that the owners of the cow, at any age of the cow, will believe that there's milk in there somewhere some day.

It's not a loan, it's actual ownership. And the expectation is that people get something out of it.

YouTube would exist almost as a hobbyist site that has issues scaling its users and monetizing its activity. At some point it would have failed because people would find it frustrating to face the lags, and the owners (who by the way are still owners, who still invested in it, so actually very little changes in this mechanic) would introduce subscription fees or something in order to use the platform. Would it have become a ubiquitous platform as it exists today? Would you have it on your tablet, tv, phone? Probably not, but any of its competitors would have gone on a very similar journey and you'd be complaining about a different company, because you need investments in order to grow, become better, more attractive, and become both the way that people choose to upload content, and the way that people choose to consume content. And it would have been YouTube who couldn't have afforded to keep the lights on at this moment.

A loan without the need to repay it.

I'm sorry, but that statement is as false as "developers get paid to much simply to press buttons. Anyone can do that".

At the heart of this statement sits a conviction that you understand the topic, while you are missing some fundamental facts about it.

Why don't you play a few thought experiments? Put yourself in other people's shoes. If you were someone who had money, why would you put it in a loan that doesn't have a need to be repaid? If you're suggesting that the entire stock market rests on the "greater fool" principle, then maybe you don't know about the end goal? Did you consider the "return on investment"? This literally is the very thing that powers the farmer who buys a baby cow, and what makes trillion dollar companies. Literally, the same instruments and calculations that financiers and CEOs of huge companies use day to day, my acquaintances who literally run their own pig farm, use every year - from options on feed, to futures on meat before even buying the piglets. The only thing they don't do of this equation is stocks, since it's a small farm and it's owned fully by the family, and they don't need to scale.