I think there's no need to discuss about Barcelona vs Napoli and Arsenal vs FC Porto, it's a sure win for both Barcelona and Arsenal, Napoli and FC Porto aren't that good compared to last season.
What I think we need to pay attention is PSG vs Real Sociedad and Inter vs Atletico Madrid, I believe most people will think PSG and Inter will win since both of them were strong in the last season, but I believe this time Real Sociedad and Atletico Madrid able to prove themselves even though they're underdog.
I have a slightly different opinion than you. I think the Barca and Napoli pair is quite unpredictable; they are the reigning champions of both the Spanish and Italian leagues. Currently, the form of both Barca and Napoli is not good, but when they face each other, the result is hard to predict. Napoli's style of play remains challenging for teams from England and Spain. Therefore, it's not easy for Barca to overcome Napoli in this round.
I believe there might be a surprise in the PSG and Real Sociedad matchup. Most people rate Real Sociedad lower than PSG, but their form this season has been quite good. I think they are even better than PSG at the moment, not just because they dominate their group with unbeaten performances.
With the depth of Barca's squad when facing Napoli it is clearly quite difficult to overcome. In my opinion, the pair of Napoli and Barcelona is one of the most difficult pairs, not only because of the difference in strength but also because their playing styles are quite opposite. So based on the pairs that have been decided apart from Napoli and Barcelona, there is still a pair that is no less interesting, namely between PSG and Real Sociedad. For me, PSG cannot underestimate this Catalonia team. Being able to become group champion means that the level of game productivity is taken into account. Furthermore, the pair Inter and Atletico Madrid and of course Porto and Arsenal are quite in the spotlight because Porto last meeting gave Arsenal 5 goals in Leg 2 without reply. In other words, this match is an opportunity for the Portuguese team to try to improve their record.