No, neither headphones nor a charger are included in the scope of delivery. Almost all providers have been doing without them for years. Only Xiaomi, Redmi and Poco phones always come with a good charger and even a protective case in addition to the charging cable, but these are Android phones.
Ja, DEP heisst aber neuerdings Apple Business Manager (ABM): https://www.manageengine.com/mobile-device-management/help/enrollment/device_enrollment_program_ios_devices.html
Why: It is probably because XR is among discontinued devices since it's been replaced by latest, newest model.
What: It doesn't differ from the 64GB and 128GB except from the storage capacity which is larger.
I have it for almost a year and my initial positive impression remains.