TLDR: Building looked a bit like a ryokan, customer service style was more like at a hostel.
The description of this place being a ryokan only pertains to how the building looks from the outside. It seems like it was recently renovated and is now run more like a (although clean and modern) hostel.
Especially for foreign travelers who have read about ryokans and are excited to stay at one, it can be a bit disappointing after having more of a hostel-experience:
Despite there being a check in counter at the building, we never saw anyone there the entire time we were there. After a long day of traveling, it is nice and helpful to be received by an friendly face at a front desk who can also help with translation issues or giving tips about the city. It is what makes the difference between a ryokan with personal attention and an anonymous hostel. The rooms contain the bare minimum; a simple small mirror or some shelves would have been helpful. Check-in was quite late and check-out rather on the early side in comparison to other stays.
Other than that: host was very quick & responsive, and instructions were sufficiently clear, the entrance to the building is nice and it smells like pine wood, most likely because it is newly renovated. It's close to combinis and in walking distance to a subway station from which you can reach shinjuku station quickly.