Objectively speaking, the differences in living environment and habits determine that the amount of exercise of wild boar must be much greater than that of domestic pigs, which means that the fat content of wild boar may be lower, while the protein content will be higher. Some experimental studies have also confirmed this point. For example, Zhu et al. found that the protein content of wild pork was 242 mg/g, which was higher than that of domestic pork (132 mg/g).
In addition, we can also see that wild boar is redder than domestic pork, which is also because wild boar has higher iron content. The iron content of wild pork is 27.4 mg/g, which is higher than that of domestic pork (10.0 mg/g). Wild pig's trotters are the best diet food for women with insufficient skin and milk, which can reduce and prevent human arteriosclerosis.
People's yearning for wild boar is more because people prefer "natural" and "wild" ingredients. In fact, "wild" ingredients are just rarer in resources and not necessarily more nutritious. What's more, sometimes wild ingredients may have some food safety risks that we don't know.