I'm making a read off of Sakurai, not myself. Face the facts, Fire Emblem characters got in because it was the new thing for Japan, and they were going to release it in America. The latest Pokemon came in because they were advertising the games that they were in. Sonic and Snake came in because there were plans for their games to be released on Nintendo consoles. Wii Fit trainer is in Smash because they recently announced a Wii Fit game, Toon Link because Wind Waker HD. Mega Man because they have something up their sleeves. Rosalina because HELLO Nintendo just recently said that soon there was going to be a HD remake of Galaxy. Sonic AGAIN because of Sonic Lost World. Ness in going to be in it because Earthbound is on the Virtual Console. I could go on for hours, for almost EVERY character!
My point is this, and this is where everything Sakurai has ever said makes sense. Smash is not a game, it's advertisement, most of the characters, (including ROB) are in the game because Nintendo was wanting to push a new game, while filling in the blanks with a couple characters that had NO purpose other than nostalgia.
The sole purpose of Smash being casual is that everyone can play it, so everybody can buy the games. If it weren't for that, Sakurai would've made this a competitive game a long time ago.
I could go on for hours. The point is: that Sakurai isn't responsible, it's the crafty corporation that is Nintendo.
But that's just a theory, a Game Theory!
Thanks for reading!