I think the problem is that it takes 30 years for the effects to start showing.

This data [1] shows incidence of melanoma by the age of 30 dropping by half in Australia, presumably as a result of a sun safety campaign that started in the late 80s (not just encouraging sunscreen but also more shade, hats, covering up, etc.). Yet melanoma rates here in general increase but it’s more and more skewed towards the older.

1. https://www.aihw.gov.au/reports/cancer/cancer-data-in-austra...