I'd say that forking is an order of magnitude (or perhaps 2) easier than creating the product in the first place. Forking is hard work. But creating a product from scratch is enormously harder.
The creators and owners have the right to decide on the roadmap of their creation. Closed source software can't deal with disagreements, but open source software can. If you don't like the roadmap, you can create your own branch or your own fork. You don't have to make use of that freedom, but it is a freedom nevertheless, available to all.