I think a trust system is the only way. Ladybird will need new/different maintainers at some point in the future. How are you going to find them now?

I don’t disagree with their choice, but it’s not sustainable in the long term.

Closed-source projects have been dealing with this forever, by having a mostly-static pool of employees replenished through job listings and interviews. A FLOSS project adopting this model would certainly feel weird, but could work if there were enough willing candidates. The question is, who will take on effectively a job without the monetary reward?

Maybe it is, if they can somehow vet potential new contributors in-person at e.g. conferences.

This is needed for more projects than just ladybird, and I'm sure will be worked out.

For now this makes sense.