This is just the case here, their performance in the preseason games isn't totally suggesting what is Al-Nassr strength as a team, and yes no doubt they did have a very bad performance time at their Pre-season games agaist playing with some of the European clubs, however I believe they have used these games to weigh out what their strength could actually be in a real time game clash with these teams and will used the stats from these matches to work things out and further having a more formidable team this season.
Some people overreact to preseason matches and they only look at the results. If it were in a real competition, it would be very natural because there they have to start collecting points. Maybe they are worried that the same thing will happen in the competition, even though all of that can be very different. I personally am more relaxed in responding to the results of preseason matches from all clubs, because I think they are in the process and they are just experimenting as a form of preparation.
Let's just see what happens in the real competition, because I have seen many clubs that failed in preseason actually play very well in the competition, and vice versa, those who played well in preseason actually played badly in the competition. We cannot immediately conclude what happened in preseason and base it on their performance in the competition they will face.
The pre-season matches are not going according to their expectations at the moment even though they are one of the big teams in the SPL, of course we cannot see their performance next season just based on pre-season results, but at least we can estimate how effective their game will be next season, we cannot be denied that pre-season and official matches will be greatly influenced by the game strategy implemented by the coach (regardless of the squad used in the match) so if the strategy implemented is effective then at least it can help the team play better even though they rely on a young squad. , and vice versa, if the coach is not able to implement strategy well, of course even by playing star players, they will not be able to get maximum results, so that's why I think if Al Nassr main problem is the current coach, because I see that tactics and His game strategy in pre-season match very messy like in last seasons.
Currently all teams will prepare their squads again to face the league, but so far Al Nassr is a team that has prepared very slowly, especially in recruiting players to improve every weakness that existed last season, and that to be honest, it makes me doubt if Al Nassr will be able to compete with other big teams next season.