Xavi would beg to differ with you.
Yes, he may pass up on some opportunities, but it's hard to put yourself in the place of the man on the field without the skyview we have on TV. Xavi doesn't look just for a single open player/pass. In his own words, he looks for "space." Sometimes that means a through ball, other times it looks too risky from his perspective (i.e. low chance of success).
Take Messi's horrible movement to receive passes centrally, for instance. Today, a couple of Barça players gave Messi perfectly good passes when he was standing static between the lines. Yes, a good opportunity to attack, had Messi met the passes and turned. However, Messi didn't move to the passes, and he was poached by defenders both times. Xavi has a good feel for what his teammates do and don't do. What may look to you like a good pass may look to Xavi like an interception or dispossession.
I thought his game today was near flawless. I saw one run by the forwards where he decided not to drop the ball over the top to try to beat the defenders, but I'll give him the benefit of the doubt. Messi's contributions to the team outweigh his flaws; Xavi, even more so.