KDB was the best creative midfielder in the Bundesliga in his only full season at Wolfsburg at age 23 before his City transfer, when had 10 goals and 20 assists. He was already on track for superstardom.He was never at the level he's at now before playing for City/Pep. He was a a well known commodity and an excellent player, but he's at another level now. I'm skeptical that if he played for some of the bum managers that Messi and Ronaldo have dealt with would improve his game.
Part of the issue with Neymar is that Messi and Ronaldo have set such a much higher bar for greatness than was the case in previous generations. Neymar compares pretty well with the Ballon d'or winners from the decade before Messi/Ronaldo started monopolizing it in 2008. He's just as good as players like Owen and Nedved and Shevchenko and Kaka were. That he's not on Messi's level is no fault of his own -- Messi is a once-in-a-century player.
Part of it is the Brazilian/Nike heritage and the hype. Brazil has been clamoring for the next great Brazilian star since Ronaldinho and Kaka faded away and Neymar was supposed to be it.
Part of it is PSG. I think Neymar really might have ascended to the truly top level of achievement and reputation if he hadn't gone to PSG, but it's just impossible to have the same popular impact playing in a non-competitive league nobody watches or cares about. HIs stats have been amazing in Ligue 1, but it doesn't really matter, and while he's played decently in some CL knockout matches he hasn't lit it up. Plus PSG has a limited organic fanbase and most neutrals dislike them. HIs transfer also screwed up Barcelona; there's a good chance Barca would have won at least one more European Cup if he'd stayed.