In this case they seem to be firmly closing the path though

> There will not be a separate process for submitting patches by other means. We do not want to create a shadow contribution system through issues, comments, email, or forks. External code can of course exist under the terms of the license, but we will not treat forks or patch dumps as a review queue for upstream Ladybird.

This does raise the question on how they are going to get new maintainers. The only thing I can think of is by active outreach to people contributing to adjacent projects that are still open. But that does not seem ideal to me as that will not yield people specifically interested and caring for the project you invite them to.

The amusing thing is that emailed patches and a listserv aren't actually all that different from github pull requests at the end of the day. In either case you're sending some code you wrote along to a group and asking them to look over it. The only real difference is the lack of a familiar web interface that's uniform across all projects and reduces friction to near zero, but emailing a patch hardly adds much friction in practice.

I think the primary difference is that it removes some of the incentive to status seek because there's no centralized network operator tracking contributions and displaying them on your profile for others to look at.

That said, the linked post explicitly says that Ladybird won't be accepting emailed patches, reviewing changes from downstream forks, or anything else. Hopefully that's not the case since entirely closing off the project would probably be an overreaction as well as jeopardize its future.