Why 'should' he have been given an opportunity? We aren't a rebuilding team. We don't have time and opportunities for subpar prospects to be gifted opportunities that they haven't earned, and even his first opportunity was one that Keefe decided to reward him with even though he was awful to the start the year in the AHL.
He sucked in his first NHL audition where he couldn't even handle garbage 4th line minutes, went back down, was wildly inconsistent but had a bit of a heater with 9 points in 5 games which earned him one more game. He looked crap in that game too, even when he was given more ice time, and the Leafs had seen enough. Traded soon after that call up for a prospect who was 2 years younger and looked significantly better than he did at any point.
He wasn't good enough, and we certainly didn't need what he was bringing to the table. Even his physicality and garbage-goal scoring, which is the only value he really brought to the table, was wildly inconsistent. The Leafs and Keefe invested in him heavily, gave him every chance to succeed, and he actually made it decently far. There were better prospects who were given far less than he was given.