Then you completely missed the point.
Oh I did not, although you seem to have missed mine. I'm distinguishing story from plot
. Robb is instrumental to the plot, and I mentioned that.
But not so much when it comes to story. This is part of the reason most of the biggest plot beats you mention regarding Robb happen off-stage.
The TV series - for better or worse - involves Robb more in the story than its counterpart. It devotes time to Robb's perspective on the war and Robb's relationship with Talisa (while the novel Robb's relationship with Jeyne is inferred and told to other people). It still elides his major military victories, although that's obviously in part because budget is a bit of an issue here.