Bedrockgames
I post in the voice of Christopher Walken
From my perspective there's a certain raw emotion to less curated creative material. Jam bands, garage rock, small independent movies. That raw visceral emotion is what I tend to think of when I think of more authentic creative experiences.
I love improvisational music, there is a tremendous release in improv. But is it more authentic? Sometimes being authentic musically means sitting and introspecting about what you are trying to say. I don't think that kind of labor and thought makes the final result less authentic. Some of the most raw and visceral emotion I've been able to express musically came when I stopped letting my fingers do the thinking and really contemplated the music (in one instance I recall spending a full day thinking about one line of melody for example). Not attacking more improvisational music at all. I think both are potentially just as authentic though. To me, inauthentic music would be when that emotion you are expressing isn't real, or if the musical ideas you express don't genuinely excite you (for example playing to an audience but without any heart).