SpaceX became profitable not all at once as well.

I think we should all remember that company's success is also a function of investors' money AND public trust. SpaceX for some people was a symbol of all things modern. Tesla as well to some extent.

With such amount of trust no wonder these finally became profitable.

Ah, also companies engineering vehicles and spacecraft are rather different from a company the whole purpose of which is matching people (readers to posters, advertisers to customers, so on).

Almost all companies are "cash negative" in their first years.

I think they're just brainwashed by our capitalist system which says that if a person is wealthy it's because they worked for it and we're successful. We are indoctrinated from very young ages to believe that capitalism is a strict meritocracy where only the best, most intelligent, most deserving people become wealthy.

In reality most wealthy people inherited some or most of their wealth, and used that inherited wealth to create more wealth- because it turns out that once you are wealthy it's really easy to get more wealthy. They aren't wealthy because they are skillful or intelligent or good at business. Most of them are good at precisely one thing: giving some of their money to a professional who knows how to grow it so that they will never run out.

Then they throw money at whatever catches their eye, and when you have billions to throw around you can cast a very wide net that will almost certainly catch something.