You’re correct in that this is a prevailing view in epidemiological/Public Health circles. But Medical Science is not only the macro but also the micro level perspective. Individual Practitioners of medicine might well appreciate more and earlier Data. A first principals based argument is a complementary approach that might uncover things that an empirical view might hide.A good example of this is the Australian Noble Laureate Barry Marshall (https://www.discovermagazine.com/health/the-doctor-who-drank...). As long as the hypothesis can consequently be validated in controlled clinical studies, a theoretical argument even without existing foundation in empirical literature can still make for good science.