There are lots of people speculating like you because the only big chances to escape is between Manchester United and Galatasaray, even though we shouldn't be able to conclude thats Copenhagen is playing badly in the Champions League. Because we don't yet know what their potential is and its true that Copenhagen managed to proved it to everyone who know there is no doubt that they are not a club that is easily underestimated by any club, including Manchester United and Galatasaray, because clubs that are underestimated are able to read their opponent weaknesses so they can exploited them to achieve victory.
Seeing Copenhagen able to qualify for the round of 16 through quite difficult obstacles is an impressive achievement because they are in a group between clubs that is quite difficult, but unfortunately its struggle may only reach the round of 16 because it looking like Copenhagen will have difficulty getting rid of Manchester City in the round of 16 knowing the gap the quality of players is far superior to defending champion Manchester City.
At the moment, the UCL round of 16 draw is out and for some teams, it's going to be a serious tussle and for some it'll be a minor jump through to the next stage. Judging based on team strength, City has a better chance to advance than Copenhagen, so does PSG, Dortmund and Bayern. For the remaining fixtures, the teams are strong and the result is just unpredictable.
Arsenal and Porto are in good form, same performance range, the probability is shaky, thesame with Napoli and Barcelona. For Madrid and Leipzig, one would say Madrid are in a better position to advance but the German side shouldn't be underrated though, they're also good in their own way. For Inter and Atletico, it's going to be a serious battle, none of them would allow the other to just go freely without making it tough. Hopefully these teams would use their home advantages wisely and to the best of their ability too.