I think that because people are informed that DKCT is more "hardcore" game in terms of difficulty, so definitely not a game for everyone, also game was launched only few years after previous game and on smaller instal base in not exactly best time for launch (February).
Yoshi Woolly World on other hand is game that can be played by everyone (has Mellow mood), visually looks way more attractive (one of the best looking Wii U games), launched on bigger instal base and in Q4 at biggest market.
Personaly, best 2D Wii U game.







