It wasn't clear to me that you were only talking about when there is only one maintainer, but it does make sense to me that the problem is _greatest_ when there's only one maintainer, sure. It still doens't fill me with confidence even when there's a junta.

With Rails, we also suspect there is one person, the original author, who has outsized authority within the plural authors, who at least occasionally, maybe more, makes final decisions without even internal discussion among the committers "committee"... but since it all happens in private, and nobody ever reveals anything about what happened there, it's hard to say how much internal discussion there is amongst the plural authors, or how often big decisions get made by fiat. It does feel very... politburo.