Visual merchandising is arranging a retail space so the products sell themselves: what is placed where, at what height, lit how, and in what context. Screens are one element inside that discipline, not a substitute for it.
Where digital adds something real is changeability. A window scheme takes a night to install and stays for a season; a screen in the same window changes between the morning and afternoon audience for nothing. That suits fast-moving categories and any promotion tied to weather, stock or time.
The caveat is that a screen among products competes with them. Motion draws the eye involuntarily, so a bright looping video next to a considered display pulls attention away from the merchandise it was installed to support. The screens that work in merchandising are usually calmer than the ones people specify: slower transitions, longer holds, less motion.
The other failure is placement inherited from the fixture plan rather than the sightlines. A screen mounted where there was space, rather than where a shopper naturally looks when they pause, is a spend that measures as nothing.