I recently did vacation at the North Sea (land side, not the islands). It was heartbreaking. In many areas the iPhone showed "No Service", in most areas we had "Edge" connection with virtually no data throughput. Even when it showed "3G" I was mostly unable to use WhatsApp. And this is a region where people live! And let's not talk about the landline broadband.... our rented appartment had a meager 1MBit download spe…
Having recently visited the Yellowstone National Park, the situation you describe for the North Sea side of Germany applies but worse, the cell phone data connection being non-existent, and with the added issue that only one hotel offered wifi, and it was out of service for the entire duration of our visit.
To me that would be what a national park ... just is.