The accountability would be in whoever promoted it. This isn't so much about accountability, as it is who is going to be responsible for doing the actual work when AI is just making a bigger mess.
The accountability will be with the engineer that owns that code. The senior or manger that was responsible for allowing it to be created by AI will have made sure they are well removed.
While an engineer is "it" they just have to cross their fingers and hope no job ending skeletons are resurrected until they can tag some other poor sod.
