IDEs can help, but they're not a panacea. There is still a mental overhead when dealing with a more verbose codebase. Not to mention increased programmer time, especially when coding guidelines mandate the creation of builders.
Another point I wanted to address is that people will tend not to fight the language. Make types harder to create than necessary? You'll have less well-typed programs. Make types syntactically light? You'll have more well-typed programs.
Getters, setters, builders, special design patterns are not related to existence of type annotations. They are related to lack of different constructions or misusing existing ones.
They're very much related to the point I was addressing, namely "What does it cost to add a new type in a language like Java". You're going to have type annotations in your signature no matter what, but adding a new type is relatively expensive.
