Sports greatness ebbs and flows with the collective memory of the fans. Part of the reason why Bill Russell is still considered one of the greatest players ever (if not the GOAT) is because, even if you never saw him play--a statement that covers most NBA fans, even those old enough to be paying attention in the 60's--you can still say "most rings."
Jordan was the foremost NBA superstar at the dawn of the new age of information--when television, newspapers, and (later) the internet were first able to provide an insane amount of coverage on a given athlete. So, if you were born in, say, 1986, and you were in to basketball, you grew up watching Jordan and grew up with the internet, where all your childhood memories can now be revisited at any keyboard. That's a huge cultural adjustment that simply didn't exist for fans of Magic, Bird, Russell, etc.
Was Jordan the best player ever? Maybe. Did was he the best player when the confluence of media and sports marketing created a behemoth of a public figure? Definitely.