By the way, there is a reason for this pattern I observed: The initial Bavarian settlement was more tribal, whereas the later settlements in areas like Saxony, Silesia etc. were already organised by aristocratic rulers. The latter didn't wanted to get rid of the locals, which they considered tax payers too and in some cases, the rulers were even non-German themselves.
The tribals on the other hand really conquered the country, and had no interest in keeping too many foreigners in their new home. That pattern in the Bavarian settlement zone is therefore more similar to what the outcome of the Slavic expansion was, than the latter German settlement of the East, the organised Ostkolonisation, which was, by comparison, much more inclusive.
Additionally, in the Bavarian zone, new Bavarian settlers came in, from the Bavarian tribespeople, whereas in many other areas we have a peculiar pattern of a large part of settlers coming from an already admixed community, picking up new locals, expanding on and so forth.
That's why even in areas like Bohemia, Northern Bohemian Germans have relatively more Slavic ancestry than Southern Bohemian Germans. The Southern areas were early Bavarian settlements, the Northern later Ostsiedlung, mostly from already colonised territories (like Saxony and Silesia):
Another reason for the pattern is the Böhmerwald region, which was very sparsely settled by Slavs and to which the pathways towards Bavarian areas were more suitable. This too caused the Böhmerwald region to be more German than some other areas of Czechia, in which more Slavs lived when the settlement began and the connections were to the North, rather than the Bavarian West and South.
The difference between tribal conquests (Slavs, Bavarians) and colonisations by states/church/rulers (German Ostsiedlung in general), if they wanted to keep taxpayers, is pretty obvious.
