Most people hate it because it brings very little that's new or particularly interesting to the table. The clean vocals are done alike most alternative rock bands of the early 21st centuary, mostly originating in the US, see the most popular being You Me at Six, Red Jumpsuit Apparatus, All Time Low, some Cobra Starship, as as for the harsh vocals, they've been prominent for years and have been done better than they are here, see post-hardcores Bring Me The Horizon, Adam Kills Eve, Alexisonfire, Underoath.
This band is very similar to Escape the Fate.
As for what I think about the song, it's not bad, it's not great. Like I said, I've heard to same material, better, elsewhere.
I'm no music expert though, there are some very interesting in depth roots of Hardcore to Post-Hardcore online, citing everything from Bowie, Siouxsie and the Banshees, Black Flag, Helmet, The Used to Enter Shikari...
Hardcore is more Hatebreed by the way, or I'd say so.