Statistically Real Madrid are slightly better in La Liga so far than Barcelona, the points difference proves that. What is most interesting is that Xavi's squad has quite complete players in every line, including pure striker Lewandowski. The reverse condition was experienced by Ancelotti squad, several key players were not available due to injury. Under these conditions, Madrid can secure full points in every match, this is the benchmark I think.
However, both of them are still the best in La Liga, when the two meet in the "El Clasico" match, it will give a full picture of who is the best this season.
Changes to the standings can occur in the following week, after all, from 3rd place and the leader of the standings only have a difference of only two points. If Madrid is held to a draw in the Real Sociedad match, that means it will provide an opportunity for the teams below them to overtake the top of the standings. or maybe vice versa, if Barcelona encounter problems when hosting Real Betis, it is the same as providing an opportunity for Madrid to widen the gap between points from them.
IMO, there's no need to wait for these two teams to meet in the El Clasico match, especially since this meeting still has a time lag. but what is certain is that the standings can change every week. We will see which team is consistent in match after match. In the Madrid camp, Ancelotti lost several players who had to be absent due to injury, including Vini Jr, who was absent for several weeks. He is scheduled to return on October 4th. Luckily, they have Joselu even though we haven't seen a stable performance from this player.
Meanwhile for Barcelona, Pedri is also scheduled to return on October 4th. for R. Araujo, his status is unknown. but now that Barcelona has Joao Cancelo, it is very likely that Xavi will include him in the starting eleven in his squad. besides that, Xavi will not only rely on Gavi to play on the wing. now, Felix can rely on Xavi for that position. in theory, Barcelona should be able to perform better. meanwhile for Madrid, the absence of Vini Jr could make Madrid's performance less sharp on the front lines. but what is certain is that we just enjoy what La Liga will offer every week.