I'm not talking in a football sense, I'm talking in his positioning in the US Market and the bizzness that this will carry for him way after his retirement.
Messi knew the team was shyte, that's why Miami has purchased many of his friends or other youngsters (if those are the right transfers, time will tell).
Chossing Miami it's perfect in terms of who is already there, Becks, and the oportunity to build sthg. from the ground in financial terms.
Doing this while at the same time he provides to his familiy a place with big latinamerican community (and even Argie one, not only the ones living there, but argie franchises, people on vacations, etc), summer all year long and without the extreme fans harrassment that he woudl face in other parts of the world.
He is just taking this like a Pro, just because he loves to play no matter what, no matter where, that's his essence. In the meantime he keeps fit for the NT and it at some point this turns into a very shitty affair in the field, he will retire/go a couple of months to Argentina or a looooong shot Barca retirement, while his Dad and co will dedicate themselves to the Messi INC and all the connectiosn he has build with this transfer and those to come.
Messi just casually allows them to have their selfie.