Why are the queries not in sync with nvim-treesitter's queries?

[viperML]

In my journey of investigating how tree-sitter works, I've noticed that the queries are duplicated here and at nvim-tresitter repo, and I see that they are not kept in sync.

• https://github.com/nvim-treesitter/nvim-treesitter/tree/master/queries/nix
• https://github.com/nix-community/tree-sitter-nix/tree/master/queries

What is that? Should neovim and other highlight program prefer any of the 2?