"Dangerous" and "damaging" and "burning" are purposely selecting awfully strong, even disingenuous, words for whatever is going on; the article only gives evidence that the anodizing dye on a heat spreader has lightened/discolored. This is probably a combination of the amount of UV that comes off of modern blue superbright LEDs and a crummy dye that easily fades. If you don't want your anodized aluminum to do this, you paint a clear coat on it.

There doesn't appear to be any evidence for anything outside of cosmetic damage. This is about as overblown as it can get.