I don't think static typing is a silver bullet here. As I alluded to in another comment a moment ago, I've seen atrocities that were committed in part because someone didn't want to have to go modify a bunch of type references, or refactor the code to accommodate a new type.

Local type inference ("var") can reduce the friction here, but, you've probably still got to explicitly declare types for parameters and return values, so there's always an excuse to be lazy.

I'd say that full-on Hindley-Milner type inference might help, except that I suspect that the folks who do this kind of thing would find a way to create even more chaos in the kinds of languages that have one.

thats not the point, the point is that you cant assume that you really know what the function is doing, too often its doing something else thats really hard to figure out without looking closely. Good code will make it so that you dont have to look closely, you can read the variable and method names.