I’m sorry, but that’s not true at all.
It’s not hard to balance it if you treat it like open source software. There’s still an owner that controls what is “official”. If you want to suggest changes, you make a pull request, as you would with software development, which either gets denied or approved by the owner of the official project. If you don’t like the direction the official game is going, you can “fork” it, call it a fork of the original if the license requires it, and you are now the owner of that fork, able to make whatever changes you’d like.
Open Source does not, at all, imply a lack of control. Blender is open source, but the Blender Foundation still has very strong control over what ends up in the codebase.
To that end, you can suggest balancing changes to the game project, and the owner of the project can approve or deny it.
As far as a paper or digital game goes, either one works. If someone wanted to print the cards and sleeve them, they can. We did that for proxy cards in Pokemon.
If someone wanted to create a higher-quality card, they could. Distribution might be difficult, but I can absolutely see someone selling a set of these cards on Etsy. That would be a challenge for whoever is interested in doing so.
The same goes for digital. The official project wouldn’t even have its own game, it would leave that to the creativity of the community and whoever is interested in doing that, and those projects could be listed by the project owner.