Boilerplate is bad because it's fundamentally just noise. When you read the code you want to be able to tell what the purpose of the code is and what the problem it solves. Ideally, code should be expressing that as clearly as possible. Having a lot of boilerplate is typically an indication that the language semantics don't allow you to express the solution in a clear way and you have to write a lot of incidental code. The more code you have to read the more cognitive overhead there is in understanding it and keeping it all in your head.