Quality, Velocity, Open Contribution — pick two. If you try for all three, you get none — the maintainers burn out, the project becomes unsustainable.
Lua and SQLite picked quality, and dropped both velocity and open contribution.
When your project is mature enough, you can afford to.
For a project like LLVM, open contribution is not optional — so you're really choosing between quality and velocity.
LLM-aided development dramatically increases contribution volume without increasing reviewer capacity.
LLM-aided review may help at the margins — catching mechanical issues, summarizing patches — but the core bottleneck is human judgment.