1. The issue here is what browsers are expecting with a <video> tag, which is long-form content and that's what they are optimizing for.

2. Depends on the browser and the player that is used.

3. Well, the <img> tag is by default much more limited, hence it is less of interested to the ad companies and the browsers allow it more freedom. But yes I agree that this is a point the browser developers should improve upon.