At the moment, it's still in the theoretical stage, I think. When they can produce the material and begin testing it, well then they can think about what it can do in the future.
Anything you can do to strengthen the body is always going to be more preferable to outright replacing a body part. To be honest nothing humanity has ever designed will every be a good as what nature has evolved. You look at, say, the heart. That simple four chambered organ can run for nearly a century if it's taken care of properly. We've barely designed an artificial one that can run for more that 1500 days. And if you look at joint replacements, well, there's a reason they prefer patients to be older - a hip replacement can last about 20 years. When you're implanting a hip, you have to cut away bone and embed almost a spike into the femur, securing it with medical concrete. If you have to replace that replacement, you have to cut away more healthy bone to fit a longer stem.
Not to crap over sci-fi fun like having a reinforced skeleton, I mean, I love the theories, but it raises practical concerns. A porous material in bone is great in strengthening the bone, but probably going to be a pain in the ass to deal with if the bone actually breaks. The whole "we can make wolverine!" is essentially the scientific communities version of click-bait, something to grab the majority's attention so they can get more readings.
