All of the monopolies I can think of are built on the back of a proprietary solution and every "patchwork of companies catering to different communities" is seemingly enabled by a standard...
Look behind and you will find that this so called 'patchwork' all benefit a small number of centralized entities who define the standards, ultimately.
True decentralized communities do not require standards. They don't require global coordination.
The problem is that you don't even realize that they exist. If you're mainstream, your idea of decentralization is actually just a thin veneer. It's often all centralized behind the scenes. Made centralized using standards and an unhealthy obsession with cooperation on a global scale. Ignoring that small-scale competition is healthy and necessary to keep everyone motivated and doing the right thing.
Then they sooner or later fall victim to a big company like Microsoft with their three Es philosophy; Embrace, Extend, Extinguish.
