The wind won't make the deflector bend.
The 2 inches of hook and loop material is what holds the 1 inch wide strap together around your leg, just below the knee. The tension on the strap can't be any more than the hook and loop can hold, being tugged on lengthwise.
Not sure the deflectors would have any effect on a rider whose motorcycle didn't have a windshield.
The Hyes air deflectors disrupt the air stream that is rushing up to fill the vacuum that was created by the windshield's forward movement. They have been found to be effective for riders who's motorcycle has a windshield or windshield and fairing.