The fact that Dortmund is at 10th place, is enough to fire Nuri Sahin to be fair. I am not really interested in any excuses or anything, Dortmund is not the type of team that should be getting anything good, we should be seeing how they are better. Think about it, this team was last years UCL finalists, and right now they are 10th on their league, that's just not acceptable at all. It was high time that they made a change and I understand why as well.
The biggest issue is, if the problem is not with Nuri Sahin and if anything is wrong with the players, then things could get a bit worse. If the players are the reason, then getting a new head coach won't make a big difference at all, it is just going to be something that will keep being a problem.
In my perspective, Dortmund's coach is not the problem that is causing them to lose league points and other competitions. Because the coach appears to be doing well, and I do not see anything wrong with the lineup. The issue is with the players, and they need to make a change and bring new players into the club since Dortmund normally perform well when they have great players, but whenever they sell a key player, they don't buy new players and instead use a few. With how Dortmund had better players earlier when all this Haaland, Bellingham, and Sancho were playing at Dortmund, you will see how Dortmund were in good shape, but they sold Haaland to Manchester City and didn't bring key players like him anymore, they sold Bellingham too no key player like him Sancho left not better replacement. So I don't think they can play coaches since the president is the one who releases monies to recruit crucial players, which I see isn't going well. Even if Nuri has been sacked and is a new coach, I do not believe the club will be able to rebound to their best form unless they bring in new players. Dortmund's performance has been so dismal that I doubt they will even qualify for the Europa League next season.