The general idea is that for something to have monetary value, it has to be scarce. Why would you ever trade a loaf of bread for something that you have an infinite supply of in the first place?

Cryptocurrencies are fundamentally a means of creating a decentralised digital scarce resource, and the Bitcoin blockchain is a rough proof of concept that it is theoretically achievable, albeit using a spectacularly inefficient method.

Artificial digital scarcity is the whole point.