Guile was deemed pretty ridiculous at first, then garbage after release. Even pros were saying he was average at best despite loops. IIRC Chris G was complaining about him for a while. Then after people put time in with him, people started saying he was good.
I mean, SFV is basic, but it's still a fighting game, and metas aren't something that can be figured out in a day. People thought Bison was good, even pros had him in the higher parts of the tier. Look at how well that turned out.
That being said, I do think FANG deserves some extra research. Homeboy is just an enigma, and it happens with every fighting game with weird characters.