Well, Satoshi's whitepaper is called "Bitcoin: A Peer-to-Peer Electronic Cash System", so it's pretty obvious what the author(s) consider(s) its main contribution to be. Arguably, the concept of a blockchain wasn't invented by Satoshi (the idea of a ledger using Merkle trees of hashes existed before), neither was proof-of-work (the idea of requiring computation as a cost of performing an action also existed, e.g. to prevent email spam). The novelty was combining all that to create a currency system and the implementation. And the motivation spilling throughout the paper is very much libertarian and goldbuggy.