Yeah I've seen a bit of it. Insane achievement.
Obviously we only get given the edited/specific bits of footage in the documentary but I have no reason not to believe the people closest to him when they say about how positive his attitude was from day one of the accident, even in the first few days of what he remembers in hospital. For such a young kid to have been racing all his life, then have that snatched away from him in an accident, and continue to be positive and make a difference to how the sport operates regarding disability and disabled participants is huge for anyone, let alone someone his age. Phenomenal individual.