It doesn't matter, the person could have made a new game from scratch since they are already going to make "new art", they already made accounts on subscribing platforms to try and profit from this, this isn't a behaviour to be encouraged.
If the other dev isn't posting everyone can just unsubscribe from his patreon, he is not holding people at gunpoint to pay him, you can even ask for a refund on patreon claiming that the person didn't offer any content on that month if you are more than a month subscribed.
This kind of stuff is what makes a lot of artists quit.