Earlier quoted context omitted.
With apps it should be very easy to find a room to rent in a shared unit, but there is no good way to do that. I've tried, and the system for long term rentals isn't as polished or usable as something like AirBNB.
There are co-living companies out there. like you said, they aren't as polished as Airbnb due to the nature of the market, because building a site as good as Airbnb is expensive as hell.
I wonder why AirBNB doesn't take the app they already developed and open it up to long term rentals. They've already done the work, it would be trivial to add in month-by-month agreements.