Category and Chronological Challenges

In answering Q&A #4, I researched "Inna-Gadda-Da-Vida" by Iron Butterfly on Wikipedia. I was surprised to learn that some of my favorite bands (Iron Butterfly, Black Sabbath, Cream, Aerosmith, Led Zeppelin, Steppenwolf, and Queen) are considered “heavy metal” bands.
Apparently, I have not categorized music that I like into the appropriate “musical genres”. I have filed them all into the single category of “music I like”. Does this make me a category-impaired person? Given what the cognitive psychological studies have shown, how would we predict category-deficiency would manifest globally in a person’s perceptual and cognitive systems integration?

Related to ease of integration of music we are exposed to in our younger years versus exposure in our “mature” years: I remember most of the names of bands and songs, and some albums that I enjoyed listening to during the sixties, seventies, and early eighties. These were my high-growth emotional years. Now I struggle, usually in vain, to recall music titles and artists of recent and current music that I like. When someone helpfully gives me some names to choose from, I often can then remember it.

One hypothesis to explain my difficulty remembering new songs and artists that I like post-1980s is:

The music that is alive during important emotional growth times in our lives becomes an inseparable part of the flow of our lives.
Therefore, greater degrees of emotional maturity are accompanied by greater limitations in facility with musical experience.
I think this is a restatement of Levitin’s work. However, I am uncomfortable with the consequential nature attending such a reality were it to be true.

A second, also unpleasant to contemplate hypothesis is:

Emotional maturity accumulates with biological maturity in a chronological fashion. The components of biological systems have been shown to become less flexible, deteriorate, and some even die out as we age chronogically.
Therefore, this rigidity, deterioration, or die off has impaired my brain and perceptual systems integration of new musical information into memory.

MY QUESTIONS ARE:

Do you know other people of chronological maturity who also have difficulty associating names with recent music and artists they enjoy? Do you find either or both of these hypotheses to be potentially valid explanations of this phenomenon?

Do you think it is possible for a person to be category-challenged? How would category-deficiency affect a person’s world view? How do you think it would affect interpersonal relationships?