When I look at Barcelona, I see Inter in 2011. An old team, over his prime to win all, with a huuuge payroll and without any young talent to build upon bar de Jong.
Barcelona need to an year zero. Badly. All their important players are over 30yo. They wasted nearly 400m for flops (Dembele, Cou, Griez). That was a crime. They have only de Jong to build upon. It would be better for both of them, Barca and Messi to part away.
I wrote a few days ago. If you are Messi, where you be the most appealing destination? The team with an excellent roster, lot of money and the coach you know, trust and was the most successful in your career. At City, Messi wouldn't need to carry the piano, they have a good and deep team. He will go as the savior who will help them conquer CL, where they disappoint year after year.
City makes too much sense. Way more than Inter. Sorry guys, we are not there. We are in the middle of "progetto" and Messi wants sure things.