Amazon Germany delivers with DPD (for 1-2 day delivery) or Hermes (for 1-∞ days delivery)
Sure, where available, but if the Swedish postal service already offers 1 day delivery, it's not a competitive advantage to Swedish companies, assuming Amazon isn't barred from using it too.
The swedish postal service is not known to be reliable, and is often joked about here in Sweden.
As an American who has come here, I gained an all new appreciation for USPS after dealing with PostNord. They really are infuriatingly bad sometimes.