For someone uninformed, what did they change? I'm able to scroll using the keyboard keys, scroll bar, and arrow keys on my keyboard. Is mobile scrolling what's broken?
I'm using Chrome on Mac OS and I can't scroll left and right in any of the code examples. This is particularly bad because the OS hides scroll bars by default under the assumption that you'll be able to scroll left and right with the trackpad.
Also, it's hard to describe exactly what the problem is, but scrolling up and down definitely feels weird and frustrating. For example, a light push that normally goes down a few lines of text on any other page seems to go down a full page. It also seems "stickier", like any scrolling takes a split second to "kick in". As a more contrived example, if I hold two fingers down on the trackpad and scroll up and down in place, any other page will scroll up and down following my fingers, but this page seems to jump around in an inconsistent way.
Something on the page is trying to intercept scroll events and do something smart, but at least on a trackpad on Mac OS in Chrome it makes scrolling feel much worse and less predictable. It looks like Chrome, Firefox, and Safari all behave differently here, with Chrome behaving the worst.
They added a TON of "inertia." Flick the trackpad a tiny little bit and it keeps moving long after I take my fingers off, giving an entirely different screenful.
Your users know better than you how fast they intend to scroll. Always.