On paper, Real Madrid looks weaker than Barcelona (especially after two defeats against Barcelona this season) so I don't think Real should be considered favourites. PSG is good, they have a very even squad, no weaknesses, but they still had big problems in the group stage, so the fact that they are rated higher than Real is absurd. All teams (except Liverpool haha) had problems, but why is PSG higher?
Perhaps the bookies' reasons for favoring Barcelona over Real Madrid? Because we know Real Madrid have been battered since they met Barcelona.
But somehow I will still consider Real Madrid as the favorite because they already have the mentality for this tournament despite the many twists and turns they have gone through.
Why is PSG higher? Because they have a consistent performance after going through the group stage.