What you described was not a “broadcast” in the usual sense, it was an experiment, like many other experiments that preceded it. It depended on three separate projection CRTs, not a single tube that came a few years later.
By late 1953, RCA got approval from the FCC for a true compatible color TV system, after they had prematurely approved and then unapproved the non-compatible CBS color wheel system.
The 1954 Rose Parade was the beginning of true commercial color TV broadcasting in the US, even though few people saw it in color. The first RCA production color TV, the CT-100, hit the market in April of 1954.
OK so it was a broadcast experiment. Happy?