BTC officially launched its mainnet in 2009

But in fact, as early as 1990, someone was working on electronic money: Ecash
Over the next 20 years, a series of experimental products such as B-money and Bit Gold were continuously iterated
Until Satoshi Nakamoto, who synthesized these efforts and launched BTC
But throughout the entire process, no one mentioned the concept of "blockchain"
Including Satoshi Nakamoto, who didn't mention it in the BTC white paper
The core goal of the pioneers has always been the same:
Create a free currency