At some point we had a brilliant junior dev who had a task to add some logic to some ES plugins in Java. When the code review went up, it was all a single Java 8 stream statement. He went out of his way to convert everything to a stream because he enjoyed the challenge I guess. It was 3 pages of nested declarations and inscrutable.

He left eventually but person was hard to work with because you had to beat back this kind of shenanigans every step of the way.