True, the problem is that AI ones are 500x longer and at a first glance look fine, so they waste much more time.
Moreover a human contributor can learn and do better in the next PR, while the AI won't, unless the prompt is changed, but the operator won't learn.
A large submission without a breakdown or explanation, or a pass to minimize the code change is junk. The operator can literally ask the ai to compose it better, refactor in to smaller PRs, or do it themself. The annoyance is to have to communicate and enforce expectations to drive by submitters. In the end every project has to figure out what they accept. If, at a glance the PR is drive by junk being thrown over the wall, a response of this doesn't meet our pr submission standards delete, or try again, to me is not overly burdensome.