I remember that, the player who made the video is a friend of mine in the French community and I helped him to make it. We labbed the entire roster for 4-5 hours and we tried to find every possible whiffing issue with Johnny. This is not an exhaustive list, even after posting the video we discovered new whiffing issues.That's what they said at MKX, remember this video?
Literally nobody cared about the hitbox issues then and I'd be baffled if they do now.
MK11 Johnny is in a slightly better state than in MKX when it comes to whiffing issues, but I think he is still the character that suffers the most from them (with Kano Dirtbag)