While this airplane crash was tragic, is has been magnified over the years, especially since Mcleans “American Pie”.
However, I would offer that this was not “the day music died”. Music continued, and in great form with The Beatles, and all that followed.
Air transportation was still a form of travel mainly for the rich, in the 50’s. Regulations, as noted in Deane’s link, were not in place.
However, I respect the fact that many historians look at this event as important. The facts are a little more realistic, and it underscores how history changes due to events, but events only skew it at the end of the day.