GPT‑6 and play custom games

"Do this not that" lists are always contextual and situational. Some of this makes sense in the context of video games. From recent ChatGPT (GPT5.6) conversations where I've seen occasional reasoning leaks into the UI, it's clear that something like this is already implemented, and I'd speculate that this is the trash they're making. Game design is really difficult. Programming a game is only a small part, and not the most important question. Why is it for sale?