I think most of the hate comes from people who played the Survival spec in previous expansion (I hear it was great in MoP but I wasn't playing back then) and basically lost the spec. If you weren't attached to the old survival then it's just another spec and there's nothing outrageous with having one melee spec.
But overall I think the implementation of survival in Legion is quite bad. I tried it out a bit and did the Mage Tower for it but I find it very clunky. It has way too many skills that are just weak fillers with nothing interesting to them. Spamming the Mongoose Bite and Flanking Strike to get more Mongoose Bites is not paricularly fun for me because of how the timed buff works, and I hate when I tried to hit one more Mongoose but missed it for a fraction of a second and then it restarts the buff, but the next buff is obviously fucked because I'm out of charges to build up again so soon. The Fury of the Eagle is also crappy because it's a channel. I literally couldn't believe that a melee spec with all instant casts has to stand still channeling. And because of how it extends the Mongoose buff it also feels kind of shitty if you get a good series rolling and Fury of the Eagle is still on cooldown. Based on the way it works, and how it doesn't do any damage without the Mongoose stacks, it doesn't even make sense to have more than 5 seconds cooldown. It's not like you can spam an ability that requires you to buiuld stacks from another ability. It should be on use for every single stack window. Traps weren't implemented in a way that they feel like a natural part of the rotation either.
I never mained survival so maybe I'm missing some of the know-how and nuance to do the rotation properly, but my impression from practicing a little bit was that I didn't like it at all.