I do not think that PSG vs Arsenal is that big, I mean bigger than most games this round that is for sure, but it's too early of the round, and we have 8 games totally this time in UCL so it will be six more games after this, so it doesn't matter if one of them wins or they draw, it will not be great and we are not going to see anything changing much, if this was a knock out stage then it would be fun but right now it is not and we are not seeing it change at all.
Plus, there are only very few teams that these bigger clubs play against big clubs, most of the games they play against are against weaker teams, so they are all expected to be doing fine, either top eight or close, so it shouldn't really be a problem to even lose.
I think it somehow depends on the result. Both teams are not the top favorites in the UCL, but if one team crushes the other with like a three goal difference, I think that would be quite insightful. If it is going to be a result like 1-3 or 1-4 for PSG, then it would have turned into a big game in my opinion. But yes I agree with you that it is not like City vs Real Madrid. But it still a very exciting game I think. As far as I know both teams are missing key players, but it is not that bad. It is not easy to see as of now where the UCL journey is heading for PSG. You can't tell from the results in Ligue 1.