well to 1.: liverpool have mascherano, who is world-class on his position, and younger. Masch and Xabi could fit together, but they have other players for that position (don't even know the names...), and IF they want to strengthen their midfield, they should get someone versatile who can cover left wing also, and that is..... surprise-surprise: barry... So xabi may be better at CM, but for pool, barry is way more useful.
to your 2nd argument: "happy to stay" is relative. Remember when we were first linked with him? he was not 'so happy to stay' back then, and i wonder why he has changed his mind NOW... He surely is not happy to be benched in Liverpool for 3/4 of the games... 'happy to stay' means nothing in nowadays football.