Meh, people like to bang on about the olympics, its really no different to "normal" athletics championships except for the fact people actually watch it
For me the 100 and 200m are just about the least interesting events at the whole olympics, but more often than not its the most watched worldwide because, honestly, length, its easy for non athletics fans, non sports fans to watch a 100m race, it fits in a news story easily worldwide while the 10k, marathon, football match doesn't.
Its "bite size athletics for the masses" , its genetics, you can win the world cup in football, wimbledon, a bunch of sports without being the best athlete, by working damn hard and learning the sport. If you aren't born to be the best sprinter in the world, you have zero chance of it. I like competition, not predefined winners based on nothing but someone being born the fastest. Everyone thought Mexico didn't have the players, that Neymar was born a winner, who performed in the final, who won? Bolt is the fastest, he's always been the fastest, he was always going to win barely tripping up, it was so obvious that people were trying to insist he might not win just to have ANY pretense that it was a real competition.
You know why they are SUCH showmen in the 100/200m, because the race itself is so boring and the result is almost every single time known YEARS before the event.
As for being a legend or not, winning a certain number of medals, one guy can compete for 8 years, have 4 injuries and miss only 4 weeks in that 8 years, and never make it to a single olympics because of those injuries, another guy can compete for 4 years, miss 3 years injured, compete in 5 competitions, and get a half dozen olympic medals.
The world acts as if the olympics is all there is in athletics, winning 100 medals out of the olympics against the worlds best and you're nothing if the guy you always beat has 2 olympic golds and you have nothing.... odd world.
In some ways I hate the olympics because of that world wide mentality, some of the greatest athletes miss the olympics and history forgets them, some guys who can't win any other competitions win in the olympics and are considered the greatest.