The issue with this theory is the crypto scam, but aside from that I would guess that this way they can keep their players engaged with the game since they don’t like sharing anything at all and gamers want everything as soon as possible

Agree, this is the only weak point of this theory

I still believe the theory that the leaks are part of Rockstar’s own advertising campaign, if there a company that know they can milk their own customers aside from Nintendo, it’s Rockstar.