The ETF has an expense ratio of 0.25% p.a.. Isn't that higher than the trading fees on some crypto exchanges?

While there is an expense ratio, it's transparent and predictable. You'll never encounter any hidden fees or complex fee structures like those on exchanges. When comparing costs, factor in the trading fees, withdrawal fees, and fluctuating gas fees. These transaction costs can quickly add up, and a moderately active investor often ends up paying 0.5-2.0% of total invested capital in annual fees. So over the longer term, the ETF's low expense ratio could benefit your total returns.