Baird got further than that. His system was used to broadcast Wimbleton tennis matches at least once. There was even a theater-sized receiver, with a huge array of neon lamps and a big mechanical commutator to scan them.

The real loss was Scophony.[1] That was a mechanically scanned system with a much brighter image. Circa 1938. WWII cut off work, and after WWII, CRTs were working better.

[1] http://www.televisionexperimenters.com/scophony.html