Are categories of taste obvious? They exist no matter what, they exist because people like different things, there is nothing but difference, or do we categorize to taste, make things simpler, to make the distinction more obvious, to tell what we are and what we are not. Good or bad? Is that it?
Is it too obvious what is mainstream? It is popular, popularity, liked, listened, watched, enjoyed, consumed, used, available, everywhere, inescapable, to be there, but I am here and I want to know what is me.
Marginal is opposite to most of that or all of that. Where is outside it is allowed to get uncomfortable, invent. What kind of people follow, what kind of talk follows. Labeling, putting people into groups, it has a role. It has a distinct part in individualizing us to be one but not, because we want to be unique and state it, identities of ours fight against community wanting to be part of the fun active buzz as strong individuals excluding community or forgetting what community does and could be. Quite a contradiction and battle.