xwOBA measures the quality of contact, taking out defense and ballparks. Because he's not at the exact point doesn't mean he was unlucky, it means 1) there is measurement error (there is always measurement error), and/or 2) there are other factors not accounted for in the statistic that account for the discrepancy.
Once again, and for the last time, reality is never wrong. It's reality. When a measurement model does not reflect reality, it's the model that is off (not necessarily wrong, but inaccurate), not reality. People underperform and overperform their xwOBA year after year. Does that mean their entire career is unlucky or lucky.
IT DOESN'T MEAN IAN IS UNLUCKY. Ian Happ isn't Charlie Brown, and life doesn't work that way.