I see the problem everyday and am just playing devil's advocate but it doesn't really do a good job explaining the "why".
They hint at Django being a different level of quality compared to other software, wanting to cultivate community, and go slowly.
It doesn't explain why LLM usage reduces quality or they can't have a strong community with LLM contributions.
The problem is that good developers using LLM is not a problem. They review the code, they implement best practices, they understand the problems and solutions. The problem is bad developers contributing - just as it always has been. The problem is that LLMs enable bad developers to contribute more - thus an influx of crap contributions.
The last section focuses on how to use LLMs to make contributions:
> Use an LLM to develop your comprehension.
I really like that, because it gets past the simpler version that we usually see, "You need to understand your PR." It's basically saying you need to understand the PR you're making, and the context of that PR within the wider project.
I think they explain "why" very clearly. They say the problem is people who don't understand their own contributions.