Have you ever tried to hit an irelia that is killing a wave in 2 seconds of Q hops? With aoes? Lmfao. Good luck with that one, especially once she can Q full HP minions without risking one not dying....
You don't seem to realize that that slipperiness in a 1v1 environment makes her nearly impossible to hit or to even lock on top with point and clicks
The only reason her win rate is low overall is, from an Irelia player's perspective, her kit is weak. When you first pick her up, I agree; you feel she is the target of every aoe in the game, because you have a tendency to try to go in and shave HP off minions to prepare them for Q's. That gets you punished.
But..... GOOD Irelias.... who have practiced ~ 50 games...... they just do nothing and let the minions do the work. They spend that time harassing with E, and using mage wave minion deaths to set up the second knife with almost perfect accuracy. When they do this, they both damage the entire minion wave, and stun the champion, and get the option to either go back and 2 second or less the wave, or to engage the stunned champion. Either way, they just won the trade, and are now back at an unaggressive nonvulnerable state, where they can just dodge skill shots and do 0 interaction until the next E opportunity.
You're basically calling E not a defensive ability, even though it's a stun. You're saying Q is not a defensive ability, even though it relocates her and takes her out of any skill as long as minion is nearby, especially if she's applied marks, and resets.
News Flash: Dash mobility is the best defense in the game there is.
In lane, Irelia dominates those mages.
It's only after lane where she has to deal with multi champion pressure that she begins to screw up. That's where CC begins to matter, or large scale aoes. Because she's taking them from all directions, and it's very hard to set up an E right in a team fight, and W is almost useless in a teamfight. She basically gets boiled down to Q + R and her marks at Team fight stage.