OK, that is quite different.
What they've apparently done there is to block scroll completely.
Then, they detect touch gestures (which would otherwise scroll
the page if scroll were not blocked!)
You won't be able to get it to work on desktop. Unless your
desktop has a touchscreen.
It's not that there is no scrolling on desktop. It's that
there's no scrolling at all. It blocks scroll and detects touch
movement and when it sees a vertical swipe, it will scroll to the
next "slide".
But there is no ability to scroll to any in-between position, and
it does not follow your finger position. When you swipe far enough, it
"triggers" the change.
This is a popular meme in web design. Do a search, and you will
find hundreds (or at least dozens!) of variants on this idea.