My 502 cents: No, I don't think so. A PhD per se does not entitle one to be be better for data mining or ML. Take kaggle's own Jeremy Howard. I would even go as far as saying that a PhD says not much about any qualification as there is a huge variability in quality of programs. Perhaps the only thing a PhD proves is for the holder to have a high tolerance of frustration.
Bottom line: If you are interested in that area, knowledgeable, creative and hard-working, why would you need a PhD? It is you that should count, not your titles.