And the locals are very pragmatic about it not being desirable to have drunk homeless people passing out and freezing to death in the winter. So, they never had a huge problem with homeless people to begin with and what little homeless people they had were take care off via shelters and other solutions already.
The "innovation" in Finland was realizing that simply providing proper housing to these people is a pragmatic alternative that actually improves their situation while lowering overall cost at the same time. Shelters cost money and they have to be staffed and when they fill up you need to spend money on emergency shelters, which costs more money. And shelters perpetuate the problem. So, providing housing lowers cost and you get a meaningful percentage of people to a level where they stop being a problem. Which frees up more resources to deal with the remaining people more effectively. And it's nice to see people get out of such a situation. Win win.
That's definitely something other countries can learn from.