For quite some time now, Dortmund has been going head to head with Bayern Munich for the title. It's clear that they're set on sticking to their strategy, which is all about the money. However, I doubt this approach will last. If they were truly open to change, they would have done so ages ago. It's clear that they're not interested in changing their ways. They would have won the title if they didn't keep selling the players they need. If they stop doing that, they will perform better and have a stronger chance against Bayern Munich.
It doesn't matter how much money they are being offered, Bayern Munich is currently a formidable force. They have the ability to acquire any player, even from their rivals. It is Dortmund's responsibility to retain their necessary players, at least until a suitable replacement is secured.
As has been the case for a long time, Dortmund don't care about their rivalry with Bayern in fact very many of their stars have moved to Bayern and some even come back when they are old there is no rivalry between them I think, Bayern with their own targets and Dortmund with their mission to be able to make money from the players they sell when they shine, these two teams I think have different visions, and fortunately the Dortmund fnas always support their team no matter what.