Crypto does not need to replace all financial activity. But it may be used in place of some activity, and opens up some new use cases that we did not have before. Somebody can purchase their coffee with fiat and their NFT (which may be an ENS domain) with an ERC20.
Take decentralized escrow, which underpins auctions, crowdfunds, markets, atomic swaps and more: it does not require a private third party.
Most traditional escrow are companies that will do data collection, long settlement windows, arbitrary thresholds, high take-fees, and restrictions based on locale.
A decentralized, open source, forkable, global, instant-settlement, ownerless, and feeless protocol to handle escrow of digital assets is rather novel.