In the entire Passion, Jesus represented every individual person, the weakest, the most vulnerable, the guilty, the poor, the abandoned. However you treat them is how you treat him in that moment. So you can try to make that argument for him in context, but then you'd have to make the same argument for every instance where you could help someone but try to argue that you shouldn't have to. If an old lady falls and breaks a bone, will you call the hospital or blame her for not taking better care of her bone health? If you find a child crying in an alley, will you bring it to the authorities, or leave it there so you can look for the mom and find a way to blame her? People are meant to be helped, not victim-blamed. That's a very large point of Jesus and the Crucifixion. Whatever you do to him, you do to others, and whatever you do to the least in the world, you do to Him.

Well nobody deserves blame for being a scrawny little weakling. However it's still technically possible to get stronger, which puts a hole in your assertion that it's impossible to improve one's own situation. It might very well be better if we help one another rather than trying exclusively to help ourselves (consider what Adam Smith had to say about the division of labor). But self-help and self-reliance still exist, when it comes down to it.