The whole thing just sounds like a gargantuan mess.
Most apps are a gargantuan mess. It's just a mess that mostly works. In a typical large scale web app written in something like Node or PHP, I wouldn't be at all surprised if 95% of the code is brought in from libraries that the dev team don't review. They have no idea about the quality of the code they're running. I don't see why adding AI to the mix makes much of a difference.
Most apps are a gargantuan mess. It's just a mess that mostly works. In a typical large scale web app written in something like Node or PHP, I wouldn't be at all surprised if 95% of the code is brought in from libraries that the dev team don't review. They have no idea about the quality of the code they're running. I don't see why adding AI to the mix makes much of a difference.