ID is excluded from science simply because it suggests no lines of research. ID presupposes that certain biological structures could not have evolved. In science this is called a null hypothesis, and the obvious response is to conduct research towards falsifying that hypothesis. (There is no way to prove such a hypothesis except by repeated failure to falsify it.)
This is exactly what mainstream science is doing, working to find naturalistic explanations for so-called irreducible structures. This is what science does. This, apparently, is not what ID does.
Feel free to falsify this post by presenting an overview of the ID research program. What are its goals and accomplishments?
"Real" science also presupposes that certain biological structures could not have involved intelligent design. This, too, is a null hypothesis. If science wants to go down a purely "falsifiable" road then it will omit valuable statements where both indiction and deduction are concerned. If that's all real science is about, you can have it.