But I gotta say it's only working for those projects because they have an extremely high barrier of entry to the code itself in the first place (working on projects like Wine and Postgres is scary, even though you can get started with easy stuff).
It also works for them because they have maintainers and core committers used to the workflow, already tooled on the workflow etc. But I wonder how much productivity would be gained by using a github-like flow maybe enhanced a bit.