Is creationism a philosophical dead-end and an intellectual cul-de-sac?

Creationism leads nowhere! Take, for example, the explanation for why certain people are lactose intolerant. People who lived in isolation for tens of thousands of years and never drank the mammary secretions of other mammals have a higher likelihood of being lactose intolerant. Ask a creationist why this is so, and they say, "God did it!" and that's the end of investigation. Ask a rational person why this is so, they'll tell you that people whose ancestors have been drinking milk for many generations have developed lactose tolerance through natural selection. This leads to further investigation and investigation always leads to discovery but creationism leads nowhere, right?