Exactly. Some ETF's will cover all possible losses of BTC, and others may offer a slightly more focused insurance. This will be reflected in the Annual Management Charge.

The ETF's will be balancing incoming and outgoing investments in the BTC markets. There will be an initial surge in buying, which will eventually calm down with profit taking and liquidation. Generally, we will see much more active volume on the buy side and sell side in the future...

Of coarse, there will be a certain balance of BTC taken out of the market permanently...