I think the main idea is that if there actually is inflation, people will(and should) move their cash to hedges and productive assets. And one of those hedges could potentially be bitcoin.
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People are already using it as a hedge, and some will indeed use it as a hedge. A better question is, how good will bitcoin perform as a hedging asset? I'm afraid we can only make guesses here, and only time will tell.
Just to add here that, at least in the Bitcoin world, there is a widespread idea that the best hedge against inflation is Bitcoin. This is simply based on its price behavior since its inception, it has been the most profitable asset. So, for those of us who believe in the future of bitcoin because of its properties, it is normal to think that it will continue to be so, but in finance it is often said that past performance does not guarantee future results.