These scenarios all sound feasible. I'm going to propose a long shot: modern musicians (almost like scholars, but not pedants) who dip back into a forgotten past and then transform their experience for contemporary audiences (Sturgill Simpson, Rhiannon Giddens for example). It's not "post x" (post-rock, post-punk, etc.) more like "pre x." There is a treasure trove of long-neglected artists--deceased but still alive--waiting to pass their wisdom on to the present generation.