Coach Brian Goorjian said in a statement that he and Team Australia "understand and support his decision."
"The best thing for everybody right now is for him to go on and develop that skill package and improve in a couple of areas for his next season in the NBA, but the Boomers are always here for him. We wanted him to know that in his time of need, the culture and the guys here are behind him and support him," Goorjian said.
Sources had told ESPN's Brian Windhorst last week that Simmons was doubtful to play in the Olympics because he planned to focus on skill development. The Australians are medal contenders who are scheduled to begin training this week in Los Angeles and play Team USA in two exhibition games next month in Las Vegas.
Simmons, 24, struggled at the free throw line in the postseason, dropping from a 60% foul shooter in the regular season to 34.2% in the playoffs. He also didn't attempt a field goal in the fourth quarter in Games 4 through 7 of the 76ers' series against the Atlanta Hawks as Philadelphia was eliminated in seven games. Simmons scored 19 total points in the final three games of the series.
76ers coach Doc Rivers said last week that the 76ers have a plan to address Simmons' shooting woes that will involve doing "the right work" and doing it "the right way."
Also last week, sources told ESPN's Adrian Wojnarowski that Sixers management and Simmons' agent, Klutch Sports CEO Rich Paul, met in Chicago at the pre-draft combine to begin evaluating the next steps in the 2018 Rookie of the Year's career.
Teams have been using the Chicago pre-draft camp to gauge the Sixers' interest in trade packages, sources told Wojnarowski, although Philadelphia remains reluctant to break up the tandem of Joel Embiid and Simmons without maximizing a return and exhausting all possibilities to improve Simmons' offense.