There has been a long standing request to split Germany into multiple price zones[1], because Germany as a single zone does not adequately match the underlying network transmission limitations and there have been multiple occasions where power flowed through neighboring zones, which in turn required both network upgrades[2] in the zones neighboring Germany and expensive redispatch[3] in the south Germany. Industry in the south of Germany fights this back as this would mean the energy prices in the south would rise (and drop in the north), as when the transmission lines are congested, the prices start to diverge.
Keeping Germany a single zone is essentially a subsidy to Bavarian industry. The industry fights this so hard that it has basically become an energy insider joke.
[1] https://www.cleanenergywire.org/news/grid-operators-recommen...
[2] https://www.pse.pl/web/pse-eng/news/news/-/asset_publisher/6...
[3] https://www.ffe.de/en/projects/potential-for-reducing-redisp...