I think labels like ‘OSR’, ‘story games’, and all that stuff are most useful when you’re looking at them from a distance. As soon as you get close, what looks like a clump resolves into a diffuse realm of variations.
Each mote is held in the cloud in a different way – some by a shared love of particular games, others by artifacts (e.g. no-photo blue dungeon maps) other by principles, others by a sense of identity, others by relationships with other members – with no identifiable center. There’s no definition that’s both precise and useful. It’s like looking for the true meaning of Christmas or something.