It does seem crazy to me too! At best the jr developer is what, half price? 1/3? A good sensible developer, left alone, for sure will get 10x or 100x the work

It does seem crazy to me too! At best the jr developer is what, half price? 1/3? A good sensible developer, left alone, for sure will get 10x or 100x the work done in 5 years. But also.... The senior developer has Seen Some Shit, and is psychologically damaged. They will resist doing things a stupid way that’s still “good enough”. The Jr. developer will happily follow orders. That’s worth something too. Maybe the 10x comes back there. Probably diversity is worth the most. And just cut out bad blood, without prejudice, when it appears.