If you're talking about in the anime, I don't really think anybody cares about him that much.
SnK Manga Spoilers:He's definitely controversial in the manga though. I never really cared either way but I always thought it was funny how much artificial depth people added to his character even when it wasn't there—some people made him out to be a true devil (island devil heh). He was a nationalist but I don't really feel like there was a whole lot more to it than that. I doubt he was Eren's best buddy either, and I doubt he was because I don't really see Isayama going back and giving us a Eren x Floch flashback sequence with only a few chapters remaining. I swear some people wanted him to be a new main character like Gabi but idt Isayama ever intended for him to be much more than a side character that advanced the plot