When Legion was going to be released, everybody said, that Ret's will be completly shit. Even more broken than in WoD. There were countless "reasons" back than, for example that "shitty" mastery, that new blessings, the remove of Hammer of Wrath etc.
Ret was literally called the worst class. Still, in M+ or RBG you have a high chance of being declined.
But why?
Ret's are one of the strongest DPS in rated Arena or PVP. The Burst is insane, the steady dmg is quite good, the healer support is the best in the game, auto bubble is amazing. PvP Ret is just very very solid.
Looking at Raids, Rets might not be the top class, but if there is a proper player behind this ret, you will be very competitive. If you have the right legendaries, you will be a BEAST. A ret being in some of the world first kills, is nothing special.
So, overall Ret is very very fine. So tell me, why did people complain about it so much?