Declassification Reform Act of 2020 This bill establishes the position of Executive Agent for Declassification within the executive branch and contains other related provisions. The agent shall promote programs and systems relating to declassification of classified information, including the development of solutions for automating declassification review. The Director of National Intelligence shall serve as the agent. The bill also (1) establishes a committee to advise the agent on matters relating to declassification programs and technology; and (2) designates various existing bodies to advise the agent, including the Public Interest Declassification Board and the Office of the Historian of the Department of State.