Senna though no doubt extremely talented and very charismatic has become a legend more because of the way he died, were there other drivers as good as him? He was the man all the crash to win drivers consider him their idol, he lasted longer because F1 became safer, had he entered the sport 10 years earlier he wouldn't have achieved legend status, he would have been dead in his first 2 years, he died because on that day he was unlucky similar to many top drivers previous to him that died.
To me the legend was Jim Clark, a driver who relied on his skill to win, no crashing into the opposition to win, no tantrums because he considered to good to be overtaken and drove anything for the fun. there aren't any like him today and haven't been for years, just a load of one car type drivers who live on their own isolated castles.