Now that Red Dead Online has had several months to build an audience, how is it faring? Quite well, apparently. During an earnings call, Take-Two chief Strauss Zelnick stated that the Red Dead Redemption 2 multiplayer component was "performing better" than GTA Online was at a similarly early point in its history. He didn't elaborate on the criteria (users? Money generated?), but it's a good sign for the company when GTA Online is still considered the cash cow.
Source: Seeking Alpha