With scroll snapping you the user have always control of the scrollable content. What you do not have control over is where it will stop scrolling. A similar behavior to forced guides in a movable element on rails (such as drawers).

This page doesn’t scroll at all, and uses the scroll as a time control for a “movie”. And that is scroll jacking, as it hijacks the scroll position to do something completely different.

This page, at least on mobile, is also guilty of implementing it in the worst way possible: without any alternative scroll indications and without smooth continuous transitions that make it clear that you are controlling the animation through the scroll.

Apple is somewhat better at doing this since the scrolljacking procedure usually brings you to an element which, at the end of a glamourous entrance, actually scrolls away with the page.