Dude, you can't compare eras!
That is exactly what every post I've responded to did...
Society was way different back then. Maybe he didn't play for the Armed Forces (we don't know this for sure) but he had a huge impact in and outside of the music scene. As mentioned previously from musical styles, fashion, dance and stage shows! Like I said, the fact that tributes are being done for the man proves he left a legacy. And that's not to slight any other artist because there are many who will deserve the same accolades!
No doubt - Prince was huge. One of the bigger musical acts of the end of the 20th century.
...but the Andrews sisters, in their day, were the Beatles/Elvis of the time... except they have more top 10 Billboard hits than either Elvis or the Beatles.