If you can't get enough of RDR2 then online is definitely recommended for you. Most of the features in the campaign is more or less included into the online portion and people will find themselves right at home in this online portion. It is insanely fun with friends but solo players can also have their fun just not as fun if you play with others.
Unfortunately, a lot of the positives of the game and its potential is undermined by several issues.
-PVP is a joke in this game. Everyone can see each other on the map. There is auto-aim in PVP. There's no consequence of dying because you spawn like 30 secs away from where you died. The pvp game modes are quite crude and don't really capture the essence of the wild west. etc
-Bugs bugs bugs. If you ever played Bethesda games then you know what I'm talking about. A good portion of my time is spent trying to workaround the many bugs in this game. Some of them are mildly annoying and even amusing but there are significant game breaking bugs in this game that have yet to be addressed despite player feedback.
-The game feels "abandoned". The last update that took place for this game was Dec 2019. 6 MONTHS WITHOUT ANY UPDATE OR CONTENT. As had been said, there are numerous game breaking bugs in this game and R refuses to even patch them let alone even address them. There is no communication between the community and R despite the community constantly trying to reach out. The rumor is that R is not going to patch the online mode until the next gen comes out which is BS.
-Some ppl have connection issues with this game as in they won't be able to play at all. My 2 friends who has the same internet absolutely cannot even create their character because it seems their net is incompatible with RDO. This is the only game where they have this kind of issue. In addition, R refuses to use dedicated servers which may ruin your net stability.
With all that being said, RDO is a good online game with tons of potential because few games can match the ambition of this game. This is unfortunate as R makes good singleplayer games but is terrible when it comes to managing online games. I'm still having fun with friends but if they don't patch this game soon then this game will soon be forgotten