Video games are rated by diverse Classification Boards all around the world. Red Dead Redemption 2, logically, was rated for PS4 and Xbox One in Australia long time ago, before its release. Now, RDR 2 has been rated again by the Australian Classification Board.
What does this mean? This fresh application could mean that the game is coming to another platform, and the logical thought is that platform is PC.
Red Dead Redemption 2 was initially refused classification, but the refusal has been rescinded, and the game has once again been rated as MA15+.