Thematically it fit fine with the SCH's kit and frankly, with the state that SCH got left in upon 4.0's release, it was the strongest bit of their new kit even if they didn't realise it yet.

The problem is that now SCH has been fixed and mostly put back to where it was before, it just further cements it's dominance over the barrier slot. There is very little tangible reason to bring Noct AST over a SCH once you factor in the overall DPS loss due to it making things harder on your other healer.