Fair play to Neymar. He was smart enough to see Barca are going down the pan and he didn't want to waste his prime years in a shit team that can't compete any longer with Real Madrid and the other teams in Europe. Especially as Messi, Suarez, Iniesta, Pique etc are all 30+ now and slowing down and a clueless board who aren't going to be able to replace these players.
At the same time though spending his prime years in France is no better, but he's got more chance of the CL, of winning the Ballon D'or if he can win CL and he'll win titles every year.
Messi should have made the same decision this summer and gone to the Prem for his last few good years. The difference is Messi loves the club, Neymar doesn't love Barca though, he never grew up here and has only played in messi's shadow.