You're arguing that every single company should be a monopoly, and nobody should ever try to compete with an existing one. Never improve anything either, unless you can do 10 times better, and only if the 10x is very complicated. Makes zero sense.

yes, and most people and businesses are "reinventing a wheel" - not sending people to the moon. Some ways of improving on current solutions to a problem is i.e. making it simpler or cheaper, and as mentioned, a complex problem can also have a simple solution.