Is BAT decentralized?

Could you elaborate on the decentralization aspect of Basic Attention Token (BAT)? Given its function as a digital currency within the Brave browser ecosystem, does it truly exhibit the characteristics of a decentralized network? Are the transactions processed on a blockchain? If so, which blockchain is it built upon? How is the issuance and distribution of BAT controlled? And does it have any centralized decision-making authorities or gatekeepers? Understanding the level of decentralization is crucial for evaluating the token's potential and security.