It works sorta-fine in Firefox. I say "sorta" because it overrides the browser's smooth scrolling to move in jerky steps on every click of the wheel, but at least it moves useably fast.

To hazard a guess, the testing environment was a Mac with trackpad scrolling. Each scrolling step on that would be small enough that "teleport to next scroll position" looks smooth, and breaking the built-in smooth scrolling wouldn't be noticeable.

I do wish people would stop trying to reimplement scrolling and just let the OS/browser do it...

FWIW I'm in Chrome 54 on Windows 7.