There is the notion that most homeless people are just poor people, otherwise rational but only in need of a little support and sympathy and they'll bounce back - usually a view informed by cherry-picked examples of people who did bounce-back, and therefore don't represent the majority of the chronically homeless population - this is the "it could be you" angle.

The other notion is that of a lifestyle-choice, treating the homeless as if they are their own indigenous demographic, choosing to live a life outside the western method, and harmed only by western cultures insistence that everyone needs to fall in line. This argument usually skips over the dependence on western societies for basic needs, and whether anyone should get to just "opt out" of society in general, while still benefitting from societal supports.

Both are true to a limited extent, but absolutely false if used as a broad defence of the homeless, or the basis of policy.

There has to be a link between the autonomy a person is allowed, and the responsibility they bear for wielding that autonomy - this applies everywhere else too, from trust within communities, to authority within institutions.

The homeless are often treated differently, but sometimes they are treated more leniently the the norm as well. If they where treated the same as everyone else, they'd still find it difficult to get a job, or loan; but they'd also end up in jail a lot more too.