I think the problem might be that it's difficult to perform experiments in economics due to the size of the thing being measured and the fact that the people making up the economy generally aren't going to be alright with you performing experiments on them.
Economics experiments are actually a thing. You can have natural experiments, or you can uncover patterns in data, or you can try controlled experiments (in microeconomics), though that sometimes just feels like applied psychology. I dunno, I've never formally studied it.
But I have read NBER papers, and can confirm that there is real research. It's not a hard science, but among the social sciences it's pretty rigorous, and often very quantitative. I know how this crowd likes it quantitative.
I would like to note that there are many other fields in science which have even more trouble performing experiments, but nobody says that e.g. astrophysics or astronomy is not a science.
