I don’t doubt that one could find a ranking that ranks any elite LAC highly in any particular field. How much weight one should put on any such ranking is of course highly debatable.
Smith has produced 25 PhDs in econ in the last 20 years compared to Hamilton’s 9. For that matter, all of the 5 Colleges except Hampshire have produced more econ PhDs, including Amherst (36), U Mass-Amherst (35), and Mount Holyoke (19).
It is absurd to suggest that OP would be disadvantaged for graduate school by matriculating at Smith.