Nah, I don't think so, it doesn't make sense since they can just do a total new game that most haven't played. SM3DW is different because only a tiny amount of its potential buyers played it, so it still has a lot of market to be sold to, and the new content if for those that already bought it to buy it again.
Having said that, I just want to remind you that there are still three 3D mario games left: 64 DS, 3D Land and Galaxy 2
"Lazyness" is for individuals, not for businesses, whatever makes money and makes sense economically is gonna be done. Whomever "lazy" is gonna get fired because companies need to make money. There may be "lazy devs", but those devs will do whatever is told to be done no matter how lazzy they feel that day anyway so not even that is an argument.