The new Airbnb regulations in Japan seem to have all but killed the service in the country. I've been planning my yearly trip, going through 6 different cities, and I ended up with 100% hotel bookings 0% airbnb. As opposed to 20% hotels 80% airbnb even last year.
Basically you need a license to host an Airbnb, and you can only host via Airbnb for at most 50% of the year. This greatly reduced the offer, and what remains has to be 2x the price to be as profitable as it was before.