He'd be as against Barcelona as Rodgers against Madrid I imagine. Depends who'll show more faith and more quickly give him better starting position, don't think he has tremendous attachment to any specific crest bar the Basques.
If you discount likes of Zidane that dont really have a position, he is the 3rd best midfielder to have played for RM in 20 years. He's only been here 2 years less than likes of Casemiro and even if not won as much, he's clearly in the pantheon. And in fact he's led his career better than most, never overstayed welcome, managed to bag the best managers to learn from. Cant say he aint a legend of noneLevels to the game, Xabi ain't Xavi, if he is wants Barcelona he gets Barcelona.
Like zidane & pep got a big club after b team management.
Xabi doesn't have that kinda pull with any club, he's a great player for a couple of teams, but a legend for none.
Going a great job though, will be at a big club soon.