I'd say the genetic histories been lost at that point. But everyone has an opinion.
Everything gets messed up with terms, like clone only, clone only covers everything. Everything was born from seeds. If I find a special plant take cuts, then pass them or sit, for me i could call mine clone only. So for me, making it seem like its special because of the clone only tag seems odd.
Maybe some day, somebody can write a post what OG really means, is via old strains with history or an S5. Or is it just cuz it has the look. Unless I can follow a family tree, it leaves a lot of questions unanswered.