A lot of hosts who post listings on Furnished Finder also post on Airbnb and end up getting most of their bookings through Airbnb but then they never update the status of the listing on Furnished Finder from vacant to occupied. I would not base an opinion solely on what you see on Furnished Finder. If you are close to several hospitals, you will likely have success with MTR because traveling nurses love 1/1 units from my experience. 

Every city is different, but I have had tremendous success with MTR in Columbus, OH. It seems that MTR is much less saturated than short-term rentals and a ton of investors still are not familiar with MTR, which means less competition. I have spoken to very successful investors and a lot of them have never heard of the MTR strategy. I would say go for it, the cash flow is amazing and the competition is much less than doing STR.

Doing research, California has the highest demand for travel nurses in the U.S., largely due to its large population and mandatory nurse-to-patient staffing ratios. California is currently experiencing a significant shortage of travel nurses, which means there should be an increase in the next decade. This means there should always be demand for MTR since the number of travel nurses should grow in CA. Hope this helps, good luck!