Thybulle was born in Scottsdale, Arizona, the son of Greg, a Haitian-born engineer raised in Harlem, New York, and Dr. Elizabeth Thybulle, a naturopath who died of leukemia in 2015. When he was about two, his family moved to Sydney, Australia, where they lived for around seven years. Thybulle did not play much basketball in Australia. He was more interested in swimming there, where he said lifeguards “were a really big deal”. His family returned to the U.S. in 2005 and settled in Sammamish, Washington, a suburb east of Seattle.

Thybulle could not make layups consistently until around the eighth grade, when his coordination began matching his speed. He attended Skyline High School for two years, then transferred to nearby Eastside Catholic, where he was ranked a four-star recruit by Scout.com and three-star by ESPN, and graduated in 2015.

The Philadelphia 76ers targeted Thybulle,leading up to the 2019 NBA draft. They were coming off a second-round playoff loss to the eventual NBA champions, the Toronto Raptors, and were seeking someone who could immediately contribute to their goal for a championship. The 76ers had Thybulle stop working out for others teams, promising in exchange to select him in the first round with their No. 24 overall pick. They effectively ended up moving up to No. 20 to select him, receiving his draft rights from the Boston Celtics in a trade for Philadelphia’s 24th and 33rd picks. On July 3, 2019, Thybulle signed with the 76ers. On October 23, he made his debut in NBA, coming off from bench in a 107–93 win over the Celtics with three points, a rebound, an assist, two steals and two blocks. After scoring 20 points, hitting five three-pointers, and making three steals in a win over the Raptors on December 8, he joined Allen Iverson as the only Sixers rookies to record five threes and three steals in a game since 1983.

On July 11, 2020, Thybulle started uploading a series of vlog style YouTube videos showcasing the 2020 NBA Bubble at the ESPN Wide World of Sports Complex in Orlando, Florida.