Firstly, I find her pick of role models quite insultingly uniform. All four are Caucasian, all four made their names as actresses and, most significantly in my opinion, all four are not only over the age of 50 but over the age of 65.
Here then are three celebrities who have chosen to ignore one or more elements of that advice. From left to right: Jamie Lee Curtis wears her natural grey short, sharp, tres chic and I would argue tres sexy too; Bridget Fonda is happy to wear her hair up and looks to be cultivating silver highlights in amidst the blonde; despite having been photographed as a blonde around the set for Our Brand is Crisis, Sandra Bullock had reverted to her usual dark tresses within days (prompting rumours that the blonde might have been a wig, as if that really matters).
Hopefully, what Renou meant to emphasise is that we might notice an increasing number of products aimed at balancing sexy and practical regardless of age and/or natural hair colour. Somehow, I doubt it though, unfortunately.