Yes, there may be some flaws in the system, which is why some teams have very strong opponents that are very difficult to survive. I am talking about PSG, Real Madrid and Arsenal of course. Even Chelsea and Newcastle are not happy about it. Because they have opponents, most of whom are very strong. They must survive in the Champions League through tough tests. Maybe we will see some teams exit before the round of 16 that are beyond our expectations.
No system can ever be free from flaws. Last season when I was doing some research and learning about the new UCL+UEL league phase format, there was a point they made about bringing tougher fixtures early in the tournament. Even last season, there were a lot of tough match ups in the league phase.
Based on what I've seen some far, each team has like 2-3 tier-1 teams to face and the other 4-5 are teams outside their leagues that they can easily defeat. Any serious team can hustle draws with those top teams and win vs smaller teams in matchups.
A couple of seasons ago, Man Utd were consider the top team in a UCL group (old format) but they ended up being the team to be eliminated first from that group. Sometimes the groupings doesn't matter that much. What about Liverpool matchups last season?