Progressive decentralization is a term used largely in blockchain communities to describe a process of moving a network from control by a centralized company or team toward control and ownership by the network's participants. This occurs through the distribution of tokens with governance and financial rights associated with them.
Some basic guides:
Progressive Decentralization: A Playbook for Building Crypto Applications - Andreessen Horowitz
When Gitcoin launched its GTC governance token in 2021, it created a mythology through the idea of "Quadratic Lands":