I don't think it's fair to say their point is incorrect. If you're talking in absolute technical terms about what "a blockchain" is in the abstract then, sure, a blockchain is immutable... but cryptocurrencies don't use…
I don't think it's fair to say their point is incorrect. If you're talking in absolute technical terms about what "a blockchain" is in the abstract then, sure, a blockchain is immutable... but cryptocurrencies don't use…