The ETF market I only a portion of the market.

ETFs can be buying while other entities like those trading on Coinbase could be selling.

Plus, most market makers hedge the delay. They don’t just sit there short Bitcoin for a day. So the ETF inflows yesterday indeed affected the price yesterday. 

 I imagine that a well informed short term trader could make a butt load with glassnode plus funding plus visibility into ETF dollar flows. plus accounts on the big crypto exchanges.