Only that Messi still had excellent alround attacking statistics. He was quite clearly still the best in terms of ball progression and chance creation on the planet even if his scorers and dribbling declined at PSG (so that he's "only" one of the best in terms of goals + assists, not the undisputed best). This is rather a case of "(semi-)retiring while you're still at the top" than anything else. Understandable but it still is a bit disappointing that he's now having field days against weaker players than displaying his abilities on the biggest stage.
Exactly, I guess the main reason is that his father and advisers told him is time to established yourself in Murica and be the face of football to the rest of your life in such a huge market while having the possibility of any sort of enterprise within the MLS (a Pele COSMOS move in a more silly and even more corporate era).
And the others are the whole Barca affair left him bitter with current management, the whole PSG Ultras stuff was too silly to bare at this age, his family (read mainly Antonella) wanting a more relax life outside the pitch, his father a more lucrative one.
Yet like you, I just would have preffererd to do a Brighton, a mid table just to enjoy himself, even if I know it doesn't work that way with his profile.
Only maybe in Argentina, but the whole "easy life" outside the pitch right now would have been impossible.
Another route would have been sthg like City, with Pep knowing what to ask and what not, but dunno how much both would have been interested in it, or even sthg like a Benfica with Di Maria...
BTW the MLS with Guille Schelotto, Becks, etc have been trying to seal this move since ages and they've done it.
The only think that it's trully annoying and that it might bother him in this new road, it's how rubbish and yellow is the Mexican and USA media, no matter if you do good, bad or so so, they are really toxic as fvck, as toxic as Spanish, Argie one or even more.
And the "funny" part is that if things turn sideways, in terms of toxic media or trully bad sporting results, he more than probably would still have a Saudi or sthg similar offer on the table if he wants and if staying fit, even a tiny shout in a late Barca cameo if Laporta is gone.
All in all, I still would have like him to still be in Europe or convincing his family to do a Newell's.
PD: The only football related thing that I liked about this move, was that he might be more rested for the NT, yet having regular football being played. But he chose a team that needs tons of work in an strict football sense (in a bizzness sense, it's like a Gold Mine to build from the very basement), too much for my taste to deal trying to fix such a malfunctioning team, I hope they sort this out fast, because if not he'll have to deal with some extra pitch effort that I don't fancy at all.