From 2000 to 2010 you won 7/11 and from 2011 to 2021 you won 9/11. No one forced to Bayern to clear out Dortmund. While oil clubs inflated the price of players this take of yours is honestly a reach mate.
This statistic paints a different picture if you just phrase it differently. From 2000 to 2012, Bayern won 7 out of 13 titles. From 2013 to 2022 Bayern won 10 out of 10 titles. While buying domestic players has been a Hoeness trait since the 70s, it only got evidently less competetive the more inflated it got.
Yes, I do think Bayern buying domestic rivals is an issue, but my problem with this argument is a) it's a drop in the ocean really and b) this argument always gets brought forth to drown out a much bigger overlying isseu that amplifies this uncompetetiveness. It is after all an issue that ALL leagues are suffering from, not just the BuLi. The only one who doesn't is unsurprisingly the league that is mainly responsible for causing this inflation.