Unless you can afford to auto-merge PRs without a human review (and regulatory controls). But that requires a massively different level of effort - auto triaging the pull requests and a functioning suite of tests (fast & non-flaky with >70% coverage).
Triaging PRs is non-trivial for a complex codebase. A good classification system would look at hotspots, blast radius, architectural complexity etc., all of which are hard to measure and we don't have good tools for these.
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no human -- code review auto-merging PRs