I wonder how good he is for the tourist trade in Japan? I bet their's a virtual pilgrimage to places associated with him. Mmmmm. More context.
A distant third after Judo, Kendo and Karate (which isn't even Japanese) - might be less than Kyudo, in numbers of actual practitioners in Japan. Not that it matters, I know of koryu where the entire art can fit in the same (small) room and have dinner together.
Like Demetrio says - no need for exaggeration.