Hamidaddin became CEO of STA in March 2020. By November 2023, Riyadh was announced as the host city for Expo 2030 by the Bureau International des Expositions. Previously, Hamidaddin served as chief of investment, strategy, and tourism marketing for the Saudi Ministry of Tourism and chief commercial officer at King Abdullah Economic City. He also holds positions on the board of trustees for Prince Mohammad bin Salman College for Business and Entrepreneurship and is a board member of the Qiddiya Investment Company, the Saudi Conventions and Exhibitions General Authority, and other government committees.