In fact, let's be honest, just a few clubs can afford him right now.
Real and Barcelona already spent a lot and can't buy new players, Juve don't need him and if he don't want to go to China and retire there, he have no choice but to stay in ManU.
Well Everyone needs him if they can sell other players.
In real Barca or Juve, he will be better than actual players so he will be needed on every team.
For example neither Messi is needed at Real but if he will go he will play and they sell another one, even hazard for him