Anyone these days is taking the defense of animation cancelling in my opinion is clutching at straws.
I used to play For Honor competitively, and there the animation cancelling is actually part of the gameplay, man, it’s even in the tutorial!
In this game the cancellation (which results in unstoppable combo sequences) is, clearly stated, an exploit.
The strongest and most unambiguous argument has already been expressed by Jelou: there is a perk to speed up weapon switching, period.
Obviously, what the developers said must also be taken into account.