Fun fact: back when Rise of the Zilart was first released, Samurai were intended to be something along the lines of a warrior grade tank, while Ninja were reduced to a light DD/puller, essentially a secondary thief but without the TH. Somewhere though someone had the balls to say "Chill out, I got this." and proceeded to tank for a bit (until he lost his shadows and likely died a horrible death). Since then, the previous dev team tried to nerf ninja so that it would be played as intended... but we are a stubborn bunch.

The new dev team however has been following this trend and even gave them this "perfect parry" you speak of. Their vision for Samurai though has remained as a primary DD, renowned for our weapon skills. That isn't to say we can't tank, it just requires better player skill, key merits, and more acute gear selection, much like a SAM/RNG needs to spec appropriately in order to be sufficient.