Actually, spinning discs cost lots more time and energy, wear and tear, than magnetically creating a faster raster system. And it could create an image which was not so much jumpin about and had faster speeds of scannin possible. It got rid of that old jumping about images found in older, moving motion pictures, too.

Because rasters were the best form, Baird was early but not a good solution. Being there with the Wright flying machine counts, but it wasn't the form Bleriot made, which was the modern propeller aircraft. Engine in front, rudder in back & flaps for turning. No need for wing warping turns, either.

Being first is good , but being efficient AND first is better. As the WRights adopted Bleriot's Aircraft structures by the 1920's.