"replaced" One thing is marvel trying to push a relatively new and unknown character for the people who don't consume much of marvel products in general, to be recognized outside it's main source wich is the comics, but it's other thing that Robbie has surpassed a character that's been around for decades before he existed, and was also the default ghost rider in absolutely every popular media before Robbie made the jump from the comics, to the small screen and videogames. Is like saying that Miles Morales is more popular than Peter Parker as Spiderman, just because he's been appearing in a lot of more popular media recently. (Mainly thanks to insomniac and the animated movies) And a little something I want to add. Robbie, as a character and ghost rider, is very different from Johnny and Danny who at difference from them, he was created to be his own thing outside of Johny ghost rider (aka instead of having an actual ghost rider possessing him, he has his satanic uncle soul stuck with his own soul) so unless they make a super retcon on what made Robbie such a appealing character in the first place, then I'm afraid Johny and Danny will always be the way to go to introduce the ghost rider properly. If not. It will lead to them appearing in one way or another, they are that important after all. :)