Just FYI for the current gen. Not that long ago, I got into the Harvard Econ PhD despite never having done a single pure math course. Just one “math for econ course”.
Things might have changed but not that much. This same advice was given back then too. It was incorrect then and still is. This doesn’t mean that math doesn’t matter. Math is very useful for econ PhDs and I wish I had done more. I would have had less catching up to do.
Zane is correct. To get in to an econ PhD, anything other than math classes or econ research is a waste of time. However I think it is sad for our profession that this is the case. Economists who write and spend time with policy makers or industry are much more influential.