Is keeping his anti-magic identity holding him back then from being easier to balance? Because most of my games in midlane are against Zed, Yone, Yasuo, Pantheon, Naafiri and other AD champs unless I ban them, grand majority of team comps are pure AD in regular play. If he is projailed by identity as an anti-magic champion, wouldn't removing him from projail be better for everyone?
I'll take fulfilling a compelling fantasy over balance every day.
Plenty of champions have successful thriving player bases even if they aren't strictly strong. There's a reason you've got Taliyah and Galio flairs and not Maokai and Sion.
And to be clear, Galio is a rock (petricite) solid 50% win rate mid laner and support right now. It's not like he's bad. He's been 47% while a priority pro pick.