During the 2019–20 season, he recorded 41 goals and 60 assists in 52 games and won the Brett Hull Trophy as the league's leading scorer.

[8] On April 8, 2022, Johnson signed a three-year, entry-level contract with the Blue Jackets.

[11] Johnson scored his first career NHL goal on October 22, 2022, against Tristan Jarry of the Pittsburgh Penguins.

[13] On July 21, 2021, Johnson was selected to attend Canada's National Junior Team summer development camp.

[15] On May 9, 2022, Johnson was named to Canada's roster to compete at the 2022 IIHF World Championship.

[17] He represented Canada at the 2022 World Junior Ice Hockey Championships, where he recorded three goals and six assists in seven games.

He has Finnish roots as his mother Anita is originally from Finland and moved to Vancouver at the age of two.