Even at it's best case outcome , Crypto will be a good complement to FIAT , keeping FIAT owners honest with relentless competition.

I was thinking about this same topic recently and the closest analogy I came up with was Shopping malls vs online stores. When online stores came alive they gave stiff competition to brick and mortar stores ,eventually closing a lot of them. Still physical stores exist and fulfill a use case but they are kept honest with the online stores.