I don't think that Dortmund will be bad this season even though at the start of this season Dortmund was not yet at the top of the standings after playing three matches in the Bundesliga. But Dortmund still has a lot of matches to prove that they are still strong enough in the Bundesliga, even though Dortmund might not be that good in the UCL, but if it's just in the Bundesliga, I think Dortmund still has to be taken into account by its opponents.
Borussia Dortmund has always sold important players, so it didn't really matter with Bellingham's transfer to Real Madrid and Dortmund will still be the top team in the Bundeliga, but it must be admitted that this season they won't be as strong as last season and also of course the competition at the top the Bundesliga standings with Bayern will not be as competitive as last season, Dortmund will still be Bayern's shadow.
But you also have to watch out for there are several Bundesliga teams that have started to develop much better this season and that is a bit of a threat to Dortmund at the top of the standings to fight for a ticket to the UCL.
Even if what you say is true, but on the other hand, something like this affects the club because losing a star player is the same as making their performance decline.
In the end they remained in the top 4 but in terms of performance they were not better and striking as before. This remains a loss because with a slick performance in the previous season there is certainly hope that this season they put more pressure on Bayern in the Bundesliga competition.
But it can't be blamed either because this scheme is always done by Dortmund and this is their strategy to bring in profits by selling some of their players for the benefit of the club.