Commonly in GTA games, we see two narratives: The success of the up-and-comer (generally whoever we're playing as) and the downfall of a big bad (whoever the villain is). We rarely get access to a window of an alternative path to success. OG Loc signifies anyone who tried their damndest to fit in but couldn't do it, so they found a different approach and made it work. He's a side effect of the GTA universe and worth exploring on that basis alone.