I did an online check before I asked. Those are normal complaints with any package delivery service, size or land area has nothing to do with customer service in this regard. Germany has rural areas too, it is not one giant city state.
The issue I see is USPS keeps failing financially. They are still not charging what it should cost for first class mail per comparison with other countries, they can’t even keep pace with new post office construction. Instances in Dallas metro area where they are storing mail out in the weather because they cannot afford or plan for new post office construction. The mass marketers flood everyones mailbox with junk mail (does that happen in Germany?). I could fill probably another 6 inches of space here. Maybe the best solution is to just sell the USPS to a country that can manage it’s postal service better than the United States.