Game of Thrones was ruined because he couldn't finish his book, but he going around writing video games.
I don't blame book readers for being mad at GRR Martin but this whole "he ruined the show!" nonsense needs to stop. He ain't been actively involved in the show in years.
Weiss and Benioff could've easily took the pieces of info he gave them (like they did with "Winds Of Winter", "Hold The Door", "Hardhome", "Battle Of The b*stards", etc.) and ended the show well. Instead they threw it in the bushes for Star Wars. That's it.
Fred.