That is the one drawback, as Medium ranks extremely high with SEO. I have quite a few pieces that will still pop up as result 1–3 with a keyword search. But, if you change the title, and aren’t optimizing SEO throughout your piece, you should be fine. I have found, though, that repurposing viral pieces from Medium often tanks for me. Better to grab pieces published on other platforms first, and then publish on Medium.