Saying it's being done badly is not the same as saying that one could do it better. Some things are hard to do, hard to incentivise, or both. And sometimes there really is a dollar bill lying in the street.
Some things also, weirdly, turn out to be unimportant. If you start a company with great project estimates internally but a mediocre product, you’ll fail. And if you make a great product but struggle to estimate feature costs internally, you’ll do fine.
It sure would be nice if we could all correctly estimate costs, but accurate estimates are clearly not essential for startups to crush it.