Why must everything be a monopoly? The biggest ecosystems of wealth has been created around open source software. Email. The Web. Linux. Webkit. Git. MySQL. NGinX. Wordpress. Wikimedia. You can build something for the world without capturing 100% of the value that results, and still have a billion dollar company. Or several, if they all have a first mover advantage. Once you have a huge audience on a platform you built, the subsequent investments can be seriously de-risked.