Age doesn't matter when referencing color.
At 20 years old or at 70 years old gender is (generally) the same. And it's often gender which plays a larger role in color preferences than age ever will.
There are tons of studies referencing color preference by gender:
http://thegeeksverse.com/wp-content/uploads/2014/09/SexOrColorPref.pdf (PDF)
https://blog.kissmetrics.com/gender-and-color/
http://www.colormatters.com/color-symbolism/gender-differences
https://www.sherwin-williams.com/home-builders/color/education/sw-article-pro-theroleofgender.html
After gender, possibly the next contributing factor may be socioeconomic status (PDF). However, user/reader age isn't really a factor when considering color.
I think your link to "Empower Yourself with Color" is all really just generalizations on age regarding anything. You can substitute practically any "taste" preference into that article/page and it still works.... "Babies cry more in a room with loud music... Pre-adolescents prefer bright, shiny music.... Young adults are open to experimenting with music... Adults tend to prefer more subdued music" I think they pulled that article out of.... somewhere. While all this is relatively true in general, as far as I'm aware, it's kind of common sense for anything not just color preference. i.e. "If its too loud, you're too old."
So, if anything age may play a role in vibrance preference, but not color.
In my own experience, demographic age has never been a factor while gender is pretty much always a factor. Once a "consumer" reaches buying age they tend to settle into the same generalized preferences for marketing. I've designed a great many direct response pieces which are often targeted to differing age demographics. As long as I'm aware of how the gender skews in the audience and design with that in mind, I've never personally seen any major fluctuation in return rates due to varying demographic ages. A piece designed for 30 year old men (or women) tends to do as well as a piece designed for 60 year old men (or women). It's when a piece designed for men is marketed towards women, or vice versa, that returns show marked differences.
Using the "Empower Yourself" over-generalization, you can see that things like MTV, which markets to teenagers and young adults, uses a much louder, in-your-face, busy design sense. Color isn't so much a factor as just "liveliness" to entice the young buyers ("look at the fast moving bright thing kid!").
If age is a factor at all it's more about general aesthetics than any specific color use. The older the demographic the less they are enticed by vibrant, busy, seemingly "loud" designs.