It was only the Copenhagen and Manchester City match that played over 2.5 goals in the UEFA Champions League round of 16 first leg. There will be more of over 2.5 goals in this second leg of the UEFA Champions League round of 16 because big clubs will be playing from home, and they will easily score many goals since they are at home.
Big teams that play at home during the second leg of the Champions League do have a greater chance of scoring more goals. But big teams who won by a few goals in the first leg also don't need to score more goals if they are able to secure themselves to qualify for the next round of the Champions League. Because there are still many rounds that the big teams have to go through with bigger challenges in the next round, so any team must also be able to protect their key players so that they don't get injured early.