Happily interested in this, I discover that they have broken the scrolling on the homepage about this for reasons. This tells me that since they have never tried their own homepage, they don't really care about usability so their product is probably not going to be very good.
As someone who had input on the website, I can say we're very concerned about that and aiming to fix it as soon as possible. Honestly, we just didn't get it right before the launch.
Why are you even doing anything with the scrolling? Something someone can do in JavaScript in a WebPage is better than the implementation in my touch pad on my Mac?
You're not wrong. But there's a tradeoff between creating a cinematic experience (which really does resonate with people in a strong way) and adhering to standard methods. We debated both approaches and went with this one, in-part because that's part of our ethos: interface design is in a local maximum, and we've had success in our software prototypes creating new interface primitives that i.e. improve the reading experience dramatically.
In order for this current design to work smoothly across platforms, devices, and input methods, however, it'll need to be re-implemented, and it was probably a mistake to try something so ambitious in the time we had available.
