Barcelona has difficulties scoring goals, while Real Madrid scored 5 goals against Atletico.
I know that some of the goals scored by Real were a little bit lucky, but that doesn't mean that the attacking players of Real are weak.
Real Madrid is the clear favorite for winning the Supercup of Spain. They will become even stronger, when Mbappe joins the squad in the summer. Barcelona probably needs a new coach and several new players. Xavi can't find a way to make the team score more goals.
If you look at the journey of the two teams, Real Madrid is the favorite to win the Spanish super champion title in the final against Barcelona. The reason is that Real Madrid won very convincingly against Atletico Madrid, even though it took an extra hour of time, the opponent they faced was a strong team, different from Barcelona against Osasuna, they had difficulty winning even though the team they faced was below their quality. In short, Barcelona didn't play well at all.
But each El Clasico match has a very different spirit. Barcelona might turn into something different in the final. Although the fact that the game was played in a neutral zone probably took some of the intensity away. So I think this EL Clasico match will be very tight. This is also a competition between Xavi and Carlo Ancelotti in formulating strategies. I think Real are not pressing as a team so the ball will belong to Barcelona and Real Madrid will rely on counter attacks and individual moments, which may or may not happen.