The world's best? Do you mean one of the best or is Neymar the best in the world in your opinion? The fact that he has been the South American player of the year over a decade ago for the last time is also proof that he isn't the outstanding player he could be. Doing some of his tricks and some great goals in Ligue 1 is really not enough to make it to the top in the world. He was the first who clearly chose money over the real club football challenge.
Are you saying Neymar is not among the best players in Europe right now? If that's what you're saying then you're not saying the truth.
However you want to look at it, Neymar would be regarded as one of the best. If you want to use the eye test, he's a fine player on the ball. If you look at the stars, he has the best stats among all the players in Europe currently.
We all know Neymar did not have the kind of career that many people thought he would have but that doesn't take anything away from him.
Talking about choosing money, players have been choosing money ever since, Neymar's was just the biggest deal at the time. The fact that he went for money instead doesn't make him a bad player.
You don't know if things would have turned out differently for him at Barcelona, so there's no point faulting him for choosing PSG when he did.