The point is.
If you had a DVD version, it won’t have you installing the standard, and the the Premium Dlx as an add-on, its just all one install. There Ms store is just pulling a file of one of their servers, and premium Dlx could just be one file, where its combined with the standard, that way you have one install, instead of multiple installs.
Still leaves the install order partially unanswered, does the Digital ownership get installed first before sim.