The finite speed of light, and indeed of all communication has various impacts on broadcasting.
Practically all communication, including broadcasting, relies totally on electromagnetic waves that may be radiated far and wide from transmitters or guided along wires, waveguides or optical fibers.
The need for synchronization rears its head in so many different endeavors that it has to be accepted as one of the great enabling technologies.
The conversion of monochrome TV to color was quite a trick, but it came at a cost.
One of the earliest and most widespread applications of synchronizing was in television.
Synchronizing became extremely important with the growth of AC power systems, which ended up being used to synchronize all sorts of equipment, from Radar to television.