Ask the person making the argument, not me. I'm just explaining their argument.

As for my opinion, homelessness(on the streets, not car sleeping or couch crashing) in the US has one primary cause, the drug crisis. This leads to a lot of people simply having a fear of homeless people, because you know, someone meth'd out can be(not always is) pretty scary and dangerous. It sort of makes the other problems worse, how do you make people want to walk in walkable cities if they're scared of being stabbed by a dirty needle? I have a separate ideological belief against drug prohibition, but sadly that has been shown(or at least seemed to) to not actually reduce drug related homelessness. So honestly, I don't know the answer, homeless people are people, people addicted to drugs are people but it is difficult for shelters to help people who have a risk of being violent to staff and other residents.