This might be the best explanation of why it is important to create an operational definition before engaging in a wide body of research on a complex topic. Whether or not you agree with the specific definition, the approach is spot on. They aren't saying that emotional intelligence or social intelligence are not important, valuable, and also can be studied. But they are different things from this.
This is my summary paraphrase of their three page paper. But I think I have captured it.
There are many skills and abilities that are important and can lead to successful, happy, valuable lives. It is useful in science to have a term that we use JUST for those cognitive abilities that are the basis for (but not exclusively) for academic type performance. They want to reserve the term intelligence for this.
They include fluid and crystallized intelligence. Mediators of intelligence, such as emotional control, motivation, persistence, and so on are important for intelligence, but they are not part of it.
Keeping terms narrow and distinct is important for research so we know what we are studying and talking about.
Citation: Hunt E. and Jaeggi S.M. (2013) Challenges for research on intelligence. Journal of Intelligence, 1, 36-54. DOI:10.3390/jintelligence1010036.