It's all in the Bitcoin whitepaper abstract: "A purely peer-to-peer version of electronic cash would allow online payments to be sent directly from one party to another without going through a financial institution." BTC no longer delivers that. It has become a high-fee settlement layer reliant on custodians and Layer 2s. BCH preserved the original vision with on-chain scaling and low fees for true peer-to-peer cash. That is why we say BTC was hijacked and BCH is the real Bitcoin.