That's clearly not what forking means in this context. You can't make the existing "instance" run different code, and it's users don't have to care if you run your own modified copy.
If a project is actually decentralized, you can't simply fork the code to fork the community. In truly decentralized systems, the consensus rules define whether one is into the system or not.
The big problem here is that most of the systems in crypto are really startups run by a small group of founders. Very few of these projects are really decentralized.
What? ENS is BSD licensed. Anyone can ‘fork’ it at any time.