Going by previous installments, it's safe to say there will be a plethora of ways to approach GTA 6. You could tackle the main story, or just explore at your own free will, or role-play, or do whatever else takes your fancy. It's all valid, and Rockstar co-founder Dan Houser believes that's the strength of this kind of game.
Speaking at the Tribeca Festival in New York City, Houser, who served as a producer and narrative lead at Rockstar for years, explains his perspective on whether you can play an open-world game wrong. "If someone enjoyed a game, that's great. If you can’t finish a story, but you loved it in other ways: Great, I don't care," he says, as transcribed by IGN.