At least with more CON, you can prevent a critical hit from snipe. 24k damage is the damage after critical calculation. The original damage is around 18k. And Im pretty sure that amount of damage already includes the bonus damage from attribute.
What you are complaining now is similar when Swordsman users have no way to beat Wizard in a fight because of CC. Now finally Archer and Wizard know how it feels to be powerless completely when they meet their worst matchup.
But okay, if you insist that skill is too OP then IMC can always reduce the damage scaling by a little or simply make some changes to basic game mechanics so CON may provide physical defense.
And you should probably realized by now that PvP in this game is like a game of rock paper scissors. Swordsman can easily beat Archer, Archer can easily beat Wizard, Wizard can easily beat Swordsman (at least in most cases). Cleric can either easily beat other classes or get destroyed by other classes.