most likely the article was written not by a programmer but by a technical writer; it contains lots of incorrect information and assumptions — result of the marketing hype around blockchains.

so called ‘smart contract’ is actually a collection of functions residing in a blockchain; it can not function by itself but has to be called from outside — by a decentralized app / Dapp.

most ‘smart contracts’ do very little more than minting their own token/coin and keeping track of the balance;