Arthur Hayes, co-founder of BitMEX, has expressed concerns about BlackRock's entry into the Bitcoin space, warning that it could fundamentally change the top crypto asset. While Hayes and other traders welcome the possibility of a spot Bitcoin ETF, he is worried about the potential influence it could give to traditional finance.

Hayes questions whether the underlying fundamentals of Bitcoin, such as privacy, censorship resistance and decentralization, could be altered if so much value and currency is owned by centralized asset managers like BlackRock. The SEC delayed decisions on several spot BTC ETF applications, including BlackRock's, in September, but is expected to rule on them by early 2024.