Well, before his two big injuries, he was absolutely stratospheric with PSG. All those talks about poker and cie are surfacing when he is injured. And i don't see why he shouldn't play poker or attend his marketing stuff when not able to play football.
Just recently, Rakitic attended an event at Sevilla right after being eliminated by Liverpool and he was all smiles. Players are not robots whose all life is only about playing football.
When you hear about some people in the know, there are a lot of footballers partying, using drugs, cheating on their partner, etc. but few have Neymar celebrity status. So, when Neymar does something, everyone and their mother know about it.
Even in Barcelona, Neymar was known for being an addict to video games (Counter Strike, PUBG) and playing poker (he has an official poker brand contract).
His first injury on his metatarsal can't be put on his lifestyle. He was hit hard on his foot. It is like saying his injury against Colombia was due to his lifestyle (he said he feared he could never walk again). The problem is that he wants to play for his nation so bad that he rushed his comeback and was not 100% fit for the World Cup. And he suffered the same injury on the same bone with PSG later on. Often, he puts priority for his country over PSG.