Board Thread:Questions and Answers/@comment-35968137-20180623203546/@comment-34651819-20190207013524

As for Star Platinum and its range, maybe that refers to its maximum effective range? Because close-range stands, after all, can go outside of the usual 1-2 meter limit but lose a portion of its power in return. It could even be a matter of energy or concentration needed by the user to get outside of its normal range, like what was noted by Polnareff when he shrunk Silver Chariot to fight Lovers. It could even explain why Dio was able to extend The World so far, compared to Jotaro.

Because he had limitless stamina as a vampire, and superhuman abilities to focus on bringing The World to such a range that it could attack Hierophant Green during the car chase scene. Of course, going by the rules of stands, it still likely lost some of its striking power. But maybe that just goes to show how far apart close and long-range stands are in their respective strengths.