It is still “extra protein” so if that’s something you think your dad could use, like if he has a crap diet, in that sense it’s a good thing. He could also take whey protein (which is cheaper, but some people have digestive issues with it), egg protein, pea protein… each of these has different qualities in terms of cost, slight flavor, digestibility, water-solubility, whether it can be cooked/baked, etc. Protein is important (especially in aging folks) so keeping the intake high is beneficial. The fact that it’s specifically collagen-derived, or whey, or egg, etc. is mostly irrelevant.