The idea that we are the descendants of people who were in the sun 10-30 minutes per day just does not make any sense. Nor does it make sense that we spent most of our time outdoors for nearly all of human evolution and now - suddenly - minimizing sunlight is essential for our health.

Today's science shows  (probably quite elegantly) how we convert sunlight on the skin into vitamin D. We don't know what tomorrow's science will show, but I think it's pretty much a given that reducing something as fundamental as sunlight to a single beneficial compound (that we've identified in the lab) is absurd.