My perspective as a maintainer is _surprisingly beneficial_ in aggregate. The changes aren't necessarily going to be the most impactful, or most visible, but I

My perspective as a maintainer is _surprisingly beneficial_ in aggregate. The changes aren't necessarily going to be the most impactful, or most visible, but I'm sure you've seen after N years on a project all the small "I'd love to fix this but can't reasonably prioritize it" items that accumulate, and someone with less expertise may often be the perfect candidate to help burn that down (it also helps build that expertise in doing so.) I can see situations in which there might be more difficult tradeoffs of "time spent vetting contributions/ramping up new people" vs. "utility per capita" but at least for the projects I've had touch on, there are always a healthy slice of up-for-grabs issues that I was/am more than happy to see get knocked off and were often reasonably self-contained, but would still contribute incrementally to the polish+overall-goodness of the project.