No he hasn't, 'World Class' should recognize some sort of consistency, Di Maria has always been a cracking winger capable of creating things from nothing but he has never been consistent and therefore never been 'world class'.
PS: World Class is a nasty expression.
(JPRouve I wanted to respond to your post from the transfer thread in here just because it's the more appropriate thread for my reply).
Look at this season, for most of it he has been poor yet his chance creation, key chance creation and assists aren't far off the likes of Fabregas. On the other hand Ashley Young has been good and even Juan Mata has had a good season, Sanchez excellent, Hazard and Silva up there too but:
Young has played 23 premier league matches with 3 sub appearances totalling 2068 minutes, he has 2 goals and 5 assists averaging an assist or goal every
295 minutes.
Juan Mata has played 27 premier league matches with 6 sub appearances totalling 2309 minutes, he has 9 goals 4 assists averaging an assist or goal every
178 minutes.
Angel di Maria has played 20 premier league matches with 7 sub appearances totalling 1645 minutes, he has 3 goals and 10 assists averaging an assist or goal every
127 minutes.
Let's compare that to Sanchez of Arsenal, Hazard of Chelsea and Silva of City because not just are they their best wide players but also who scored gave them an average rating that was
considerably higher than Angel di Maria for this season.
David Silva has played 32 premier league matches with 0 sub appearances totalling 2661 minutes, he has 12 goals and 7 assists averaging an assist or goal every
140 minutes.
Eden Hazard has played 38 premier league matches with 0 sub appearances totalling 3379 minutes, he has 14 goals and 9 assists averaging an assist or goal every
147 minutes.
Alexis Sanchez has played 34 premier league matches with 1 sub appearance totalling 2953 minutes, he has 16 goals and 8 assists averaging an assist or goal every
123 minutes.
Of course take statistics with a pinch of salt but you get my point, depends on how much you value productivity. Young for example has probably been better defensively and Mata at keeping possession. Sanchez, Silva and Hazard have obviously performed better than Angel di Maria overall but if you value the productivity of a player highly then there is the reasonable argument Angel di Maria has been consistent because even when he has a 'bad' game he produces things.
When United were winning in their final season under Ferguson they were praised for their ability to consistently win despite sometimes playing poor, it was said that's what champions do. In the second part of last season when Chelsea managed to win games despite playing poor sometimes it was said that's what champions do. I don't think it should be held against Angel di Maria that he is productive but has more poor games than most world class players (since he is still productive in those games) just like 2013 United or 2015 Chelsea are not any less of a team just because those respective sides were very clinical but their performances weren't exactly great.