As someone who has played Knack on hard difficulty I hate to inform you sir that your opinion is wrong. There is no conclusive reasoning to say that Knack is better than Super Mario 3D World.
Sales don't make a game better. I would argue that many PS4 folk bought Knack out of desperation of games and you fell for the "but it's not that bad" game complex people get with bad games.
here's a very opinionated micro-review:
Story: 5/10
Gameplay: 1/10
Style: 5/10
The story is fine, if it wasn't filled with so many damn plot holes... This irritates me greatly
The gameplay lifts directly from other Sony franchises. Not to mention it has a constant issue of slowdown-death. The game isn't very responsive at all and it was very unimaginative in parts. It's a puzzle game that tries to be a platformer but fails in both aspects.
Style: It was a horrible art direction. Personally i believe the game would have looked better with a cartoon filter. Something Ni No Kuni like
Mario on the other hand nails all these categories with higher ratings. Nintendo has never made a platformer that isn't bad. Had consistent replay-ability and a defining art style that looks even better in HD.
I usually never tell people their opinions are wrong, but in this case, knack is so bad it's on Duke Nukem Forever's level of bad.
For clarification:
http://www.metacritic.com/game/pc/duke-nukem-forever
http://www.metacritic.com/game/playstation-4/knack
