[lo_zamoyski]

The difference is not in the claim "good for somebody", full stop, but your relativistic and subjectivist take as well as your distortion of human nature.

A person with pika desires to eat things with no nutritional value, like glass or polystyrene. A drug addict desires drugs. A pedophile desires sexual relations with children. These are disordered desires that do not advance the good of the subject: eating glass is not good for you; taking drugs is not good for you; having sexual relations with children is not good for you (both the sexual act in itself, but also that harming children like that is gravely opposed to justice and our social nature).

In the case of an armed conflict, our social nature entails justice, and so we can determine the moral features of a war according to justice. We can objectively say that the Russian invasion, broadly, is gravely immoral and that the Ukrainian defense of their country, broadly, is moral (it is still possible for Ukrainians to engage in immoral acts as part of their defense, of course).

W.r.t. universal health care, this is not something that is intrinsically evil, and so whether it would be good to institute universal health care will depend on particular circumstances. That there is debate over such things does not imply that there is no objective fact of the matter. Indeed, if that were the case, then genuine debate would be impossible, as genuine debate presupposes an objective truth. It would be nothing more than a battle of arbitrary wills willing things for no reason.