No, because they have a demonstrable mechanism from pre-established science: UV radiation damages DNA, which causes cancer. Their product absorbs or scatters UV radiation.
This is the same as the teeth flossing skeptics: observational studies suggesting a paradox are interesting, but they actually need to unearth convincing alternative models with at least as much support as the dominant one for why they're right.
This is the same as the teeth flossing skeptics: observational studies suggesting a paradox are interesting, but they actually need to unearth convincing alternative models with at least as much support as the dominant one for why they're right.