When Roger Bannister broke the 4-minute barrier using pacemakers, John Landy recognized immediately that, even if Bannister had violated rules against pacemaking, the bell could not be unrung, and Landy's subsequent mile record forty-six days later -- in a time faster than Bannister's, and in a "proper race" without pacemakers -- would not be seen as the first sub-4 mile. Landy was right. In the popular mind, Bannister would always be the first sub-4 miler. Outside of Australia and a small collection of hardcore track fans, Landy became little more than a footnote (and the guy who lost to Bannister in the Commonwealth Games later that year).
But not many people care about Gatlin's fan aided 9.45, which was faster than the existing world record of 9.58.
He broke the 9.5 second barrier too, but perhaps it was not as special as breaking a nice whole number like 4 minutes, 2 hours, or perhaps 9 seconds.