Red Dead Redemption 2: They're not making DLCs outside of online mode

Red Dead Redemption 2 will not receive DLCs for the campaign mode, for now. They are focused on making the online mode have content.

GTA V didn't have any additional content outside of its online mode. The answer is simple: GTA Online was too profitable to dedicate time to anything else. How could they justify developing additional story content when they could create missions and a casino? Now, it seems Red Dead Redemption 2 will suffer the same fate.

DLC only for online mode in RDR 2

The medium VG 247 was able to speak with Rockstar Games, and ask them about the future of Red Dead Redemption 2. And the answer they received was that they are totally focused on having something new for the online mode.

Unlike GTA Online, Red Dead Redemption Online's servers haven't seen much player traffic and haven't generated as much interest, so the developers are focusing all their efforts on providing content for Red Dead Redemption Online. They recently released a character role update to add variety, but it doesn't seem to have significantly revived the game.

Although this is something that was already destined to happen. We once had GTA IV expansions with Lost and Damned and The Ballad of Gay Tony, and in Red Dead Redemption we had Undead Nightmare. Very ambitious expansions that showed that good downloadable content could be made at a time when the usual feeling was that they made minimal effort. But now the money comes mostly from games as a service to which they sell microtransactions so that they can buy cosmetics and play in virtual betting houses. Creating a new story would be very expensive compared to the potential of putting more missions and clothes online.

Source: VG 247