LAS VEGAS—One of the most exciting things I’ve seen at this year’s CES tech show was a man putting a TV together. It looked more like he was hanging photos. He’d grab square tiles off a pile, attach them to the wall, then screw a small plate up top. A moment later, the surface would spring to life. He’d attach another, and it would extend the picture. He built a TV one tile at a time, and it looked awesome.
This particular set was a prototype of a new Samsung modular TV project. At CES, the company displayed screens as small...