This is a big problem in open source that seems taboo to discuss.

In my opinion, unwritten rules are for gatekeeping. And if a new person follows all the unwritten rules, magically there's no one willing to review.

I think this is how large BFDL-style open source projects slowly become less and less relevant over the next few decades.

Agreed. The level of aggressive gatekeepers is just crazy, take Linux ARM mailing list for example. I found the Central and Eastern Europeans particularly aggressive there and I'm saying this as on myself. They sure do like to feel special there, with very little soft skills.

This will likely be alleviated when Ai first projects take over as important OSS projects.

Fir these projects everything "tribal" has to be explicitly codified.

On a more general note: this is likely going to have a rather big impact on software in general - the "engineer to company can not afford to loose" is likely loosing their moat entirely.

In the small, it's still a meritocracy. A patch like this is obviously correct and I expect to get in first try (maybe with a formatting fix by the maintainer).

For large works, the burden shifts, since you are increasing the maintenance load. Now we have the question of who will do the future work, and that requires judgement of the importance of the work and/or the author, and hence is a fundamentally political question.

Can confirm that it also happens in other complex systems! Still a lot of good time and the novelty factor helps with pushing through

Is this discussed in the article? How hard was to deal with the unwritten rules in this case?

Sand that after so many years these rules are still not written down.