I have bought the Premium Deluxe DVD box version (Amazon Gernany, 95€). The Standard Version was already installed (active Game Pass Ultimate).
The only thing I had to do was enter the key (from the keycard in the box) in Microsoft Store.
The key was accepted, no download was required and I started the Simulator. In the Content Manager 20 new packages showed up and I downloaded all 3.79G. The new content works fine. Purchase options in the Microsoft Store and the XBox App (PC) are no longer available, it is indicated that I own the product.
My Simulator starts as usual, WITHOUT a DVD check. I have never inserted one of the 10 DVDs into the computer.
It seems the DVD installer puts a different launcher (with DVD check) into the system.