Correlation between IBIT and BITO is 1 so there shouldn't be much of a difference in volatility https://portfolioslab.com/tools/stock-comparison/IBIT/BITO I'm not a day trader so I can't speak to trade by trade volatility between the two. I guess anyone buying BTC directly or indirectly would be reducing the availability, last time I checked ETF's were holding about 4% of global supply