If we exclude AI art assets from that criteria, wasn't AI also used for coding in Mecha Chameleon, which recently achieved big success? Quite a few games have AI code in them. I know of a Korean game company too. It's just that labeling yourself as having used AI is marketing-negative, so it hasn't become widespread.

Just recently, someone used AI code to fix a Unity engine bug and hand-wrote the rest, and it still caused a huge uproar. It's a world where honestly disclosing that you used AI code is not a good idea.

I'm not talking about using AI to help code, which seems obvious, the parent commenter is talking about people building game engines and assets from scratch in a weekend. Meccha Chameleon was built on UE5[0], and Big Walk (the game you're talking about where the devs solved a bug using AI) is using Unity. Both of these games, I believe, took longer than a weekend to create.

[0] https://www.unrealengine.com/developer-interviews/meccha-cha...