Barcelona tried their best in this match, though Atalanta did well too, and they tried their best to see that they win the match, but unfortunately it ended in a draw. I think this could be a very good result for them if they win the match, although the result did not affect Barcelona since their position in the table is still okay. But Atalanta were trying their best to see that they win so they will qualify. But you are right; they can still do better in the coming round. Since they are not a weak team.
a draw would not have much effect on Barca, but for Atalanta, a draw is the result they actually avoided. with this, they have to fight in the playoff match. it will be interesting because some strong teams like Man City, Munich, Madrid, PSG, Milan, and Juventus are also there.
the match that is done together does make the match more interesting. although in the end, the team that is certain to qualify may give a surprise result like the PSV vs Liverpool match which ended up being Liverpool's first defeat in the UCL.