I agree. I would say that Erlang goes ~80% of the way compared to Haskell's type system and the last 20% really matter, to the point that in many cases I find m

I agree. I would say that Erlang goes ~80% of the way compared to Haskell's type system and the last 20% really matter, to the point that in many cases I find myself not really using Erlang's (optional) type system at all. Better type coverage and more descriptive types allow the compiler to infer more and I'd say this is the opposite of diminishing returns.