in my opinion Inter will be able to win this final, they are too determined to lose this match, they have beaten all the strongest teams and they arrived in Monaco with the awareness of being a great team, it is true that now PSG is much stronger and is a much more compact group, but I think that this Inter is unbeatable
I don't think you are underestimating PSG, but the way you are judging them makes it seem like Inter are unbeatable. Remember, this is the final match, PSG strength is also not as weak as imagined. In addition, Inter is competing with Napoli in the hunt for the Scudetto, in conditions like this, Inter players are very vulnerable to injury if Inzhagi continues to force them to play full time in every match.
Luis Enrique is also trying to become the first coach to give the UCL Trophy to PSG, besides he also wants to follow Guardiola who managed to achieve the Treble Winner with different clubs. Currently the chances of both teams are still 50:50.
Nothing can be underestimated in the final match later but everyone has their own speculation to determine the choice or hope for the favored team.
In terms of overall quality, Inter Milan and PSG have no difference but in terms of mentality and experience Inter Milan is slightly better than PSG, maybe that can be a reference.
But personally I prefer a new champion in the UCL competition this season, even though it is a bit difficult but there is a chance for PSG to win the title.