There's a lot of different aspects to a good touchpad experience but from my knowledge linux distros do not implement smooth scrolling, apps have to do it individually
responsive, high fps scrolling instead of big discrete jumps. Makes it feel like there's a direct connection between your finger movement and the content on screen. I'm guessing you're either using mainly apps that already have decent smooth scrolling or maybe you just aren't sensitive to it. There's also kinetic scrolling, where stuff will keep moving after your finger lifts as if it had momentum, the acceleration profile and some other stuff. I'm not sure how much this post covers
Interesting. Probably I'm not sensitive to it. Most of the stuff I scroll through is code and it would annoy me to no end to have it scroll and show me half a line at the bottom and top of the screen.
Just noticed that my browser also has smooth scrolling enabled (by default I assume) and turning it off, I see the difference. But given I have apps that don't and never noticed means it never was important to me.