Tbh if your Barcelona or Madrid then the majority of the games you play in the league are vs far inferior opposition. While there is a luck of the draw in the UCL there is also far better opposition.
Moreover in the league you can lose a few games or draw a few games and still end up winning the league whereas in the UCL if your team has one bad game you can potentially be out. I think both league and UCL have their difficulties
The height of El Clásico, Ronaldo v Messi and arguably the two most dominant teams of the last decade or so. However which team was more successful during this time period.
Tbh if your Barcelona or Madrid then the majority of the games you play in the league are vs far inferior opposition. While there is a luck of the draw in the UCL there is also far better opposition.
Moreover in the league you can lose a few games or draw a few games and still end up winning the league whereas in the UCL if your team has one bad game you can potentially be out. I think both league and UCL have their difficulties