If I had that kind of influence, I'd make hockey pucks white.

After reading the article (and others), I think this is giving him too much credit.

He was the BBC studio controller at the time and pushed to have the matches broadcast in colour. The BBC ignored him for years and then suddenly changed their minds without reason, and in 1967 they ordered David Attenborough to do the next Wimbledon in colour.

However, the colour of the ball wasn't changed. Balls remained white even while being broadcast in colour.

Yellow balls had actually already been used since the 19th century, but not consistently, and not at Wimbledon. After a few years of tennis matches being broadcast in colour, the ITF (without David Attenborough's involvement) conducted a study and found that flourescent yellow balls were easiest for viewers to watch, and so they started being used at Wimbledon starting in 1972.

he decided to change the tennis balls from white to yellow for easier visibility
That's not what the article says, the article says that he was one of the people pushing for Wimbledon to be broadcast in colour, which resulted in the International Tennis Federation doing a study to determine the optimal colour for the ball for easier visibility on a television screen which they decided was yellow.

GREEN.