It's not a denial of service attack for them to scroll more than a typical user. They don't allege it is such an attack either. If X is correct, they certainly

It's not a denial of service attack for them to scroll more than a typical user. They don't allege it is such an attack either. If X is correct, they certainly went to some effort to make the screenshots and its somewhat of a synthetic test because they only follow brand accounts and hate accounts – but that would be the first way you'd test such a hypothesis and X did in fact serve them the ads next to that content.