I do definitely believe people can be too broken to fix in certain ways. I feel like this about some parts of myself. But the thing is, that we can't say someone is too broken to fix as a whole, because the paths to be are virtually infinite. So that's why most people intuitively lean towards "you can't never lose hope". I'd say they are intuitively right this time, and yet people can also be too broken to fix in some ways. They are not mutually exclusive.

Now, that doesn't say much about whether one should try to overcome trauma or try to bury it. That depends a lot on the context, the direction you would like to move towards and the support you have to do it.