Finland went all in on the "Pathways Model" and have essentially eliminated homelessness in their nation. An interesting read about it here:
Finland's homeless crisis nearly solved. How? By giving homes to all who need.
The optimal solution, a group of four experts appointed by the Ministry of the Environment found, was Housing First. “Solving social and health problems is not a prerequisite for arranging housing,” they observed. “Instead, housing is a prerequisite that will also enable solving a homeless person’s other problems.”