It is understood British Gymnastics wanted to focus on winning a team medal, rather than take a specialist to the Games.
An appeal from Downie’s legal team against her omission was rejected last Friday.
Downie’s younger sister Ellie, 21, the 2019 world bronze medallist in the vault, had already made the decision to take time out from the sport after the sudden death of their brother, a talented cricketer.
Becky Downie made her Great Britain debut in 2006 and has won a total of 14 senior medals across her career, representing her country at the 2008 Olympics in Beijing and again at the Rio Games in 2016.
The former European champion, who underwent ankle surgery in 2018, had delayed her retirement for one last attempt at her first Olympic medal, believing her routine was good enough to win gold.
Last year, the Downies said abusive behaviour in gymnastics training became “ingrained” and “completely normalised”.
But British Gymnastics’ Thomas defended the decision not to select Becky Downie.
“There is no athlete who was viewed in any other light around speaking out over the last 12 months that impacted on selection,” he said.
“I’m very confident the team were considered on their gymnastic merits and nothing else.
“In terms of Becky and the additional opportunity we put on for her due to tragic circumstances, we worked with Becky to offer that opportunity, and it was not a forced opportunity.
“At that point we hadn’t decided on the [prioritisation] of the team [event] because that was for the panel to do at the point of nomination.
“We felt that was the right thing to do in the circumstances – to allow Becky to finish her trial opportunity and then to consider her performances alongside all the other gymnasts.”
