The cyclist moved to Australia when he was nine years old and was noticed in Western Australia as a young prodigy.

The announcement appeared to have caught many off-guard, with Richardson an important member of AusCycling.

Speaking on the ABC Sport Daily podcast, Bates said there was a strong sense of disappointment that Richardson was defecting after years of AusCycling allocating him resources.

"There's a lot of people this morning who just can't believe it and some who are feeling, personally, quite let down because they were blindsided by it," she said.

"Others who are feeling a little bit ripped off because supporting him over the years has come at the direct cost of supporting other athletes."

In Paris, Richardson won silver in the men's keirin and men's sprint, and a bronze medal in the men's team sprint with Matt Glaetzer and Leigh Hoffman.

The 25-year-old said he had not taken the decision lightly.

Bates told ABC Sport the decision to switch nationalities was well within Richardson's right and he should be allowed to if he felt a strong connection with the country of his birth.

But the former cyclist questioned why he chose now to make the move and not much earlier in his career and before making Olympic teams.

"I think the tie to your country is very strong but, in saying that, if there is that tie, then I'm not really sure why he wouldn't have made this leap years ago," she said.

"It doesn't really sit right with me that if that was the case all along why he went down this path with AusCycling."

Richardson represented Australia at the Olympic and Commonwealth Games as well as world championships.