2 million copies of this game has already been sold since it was released on the PC on 2012. A Mac version is on the way. One reason for the non-release? Too much work. In the first Torchlight game, the developer was able to port everything to the consoles directly. This time, it will be no easy task and that it can be a hard business decision to make.
I also think that now that the Xbox One and PS4 are coming, other decisions that have to be made by company include porting the game to current-gen or next-gen consoles. It’s probably a wise move to not port the game at this time. But maybe later.