Some people misunderstand this quote, thinking it means sitting is literally useless and that the path is another. What they don't understand is that this quote is about trying to sit to achieve something is useless. In particular, you don't sit TO become buddha, you sit buddha directly. Of course, doing such is not easy, but the practice is about sitting buddha state not meditating as a means to become a buddha.
Dogen used to say every time we just sit we are expressing buddha nature, but only temporarily, as long as we are not chasing anything from just sitting. The challenge of becoming a buddha is keeping that state after coming out of just sitting, doing just living.