BlackRock doesn't really care whether Bitcoin is gold or crap; it profits from management fees (Expense Ratio). As long as the scale (AUM) is large enough, even if Bitcoin halves in value, as long as people continue to buy and sell through it, it makes about 0.25% in fees annually. For them, staying aligned with the index and avoiding redemption risk are top priorities. "Buy low, sell high" losses are investors' money, not theirs.