Hacker News Reader

Who decided the block size? Who decided to adopt SegWit?

Not the miners. They’re only one of many parties with influence over Bitcoin development.

Miners are the only people who decide the rules of Bitcoin. They vote with their mining power. (this is in the paper)

Bitcoin isn't bound by the white paper.

> Who decided the block size? Who decided to adopt SegWit?

Users running bitcoin nodes doing transactions validations, not miners creating transactions.