I love George but I don't want to go "all in" on him or any player what - one year removed from a season long injury. These injuries are a play away from happening again. You can't mortgage your future with that possibility. Maybe it never happens again hopefully for him but look at Jabari Parker, now Embid has another injury. I don't want any damaged goods.
Well, depending on what you mean by all-in I probably agree with you regardless of the injury or not (the C's trade chest should be enough to land two high-level players if you fully exhaust it, giving up everything for one guy is simply unnecessary), but George's situation is a little bit different. He broke a pretty big bone in his leg on a freak play, it's a little bit different than a guy playing on rebuilt ligaments or a stress-related break of tiny foot bones. I'm not so much concerned about George's injury history as I would be putting the pieces needed to compete around George (and Isaiah and Horford, yes).
That being said, Bird isn't trading George, so it's all moot