The rule could be phrased better in terms of what should be in the same repo: A depends on C therefore A must be in the same repo as C. B depends on C therefo

The rule could be phrased better in terms of what should be in the same repo: A depends on C therefore A must be in the same repo as C. B depends on C therefore B must be in the same repo as C. THEREFORE by logic A and B must (or should) be in the same repo too. But so in general is this the right direction to be thinking about what all should go into a single mono-repo? And what about big companies who are said to have "everything" in a single repo? Does that make sense?