I work in homelessness. There are many homeless people who reject offers of help. Plenty who have housing, whether it's a social housing tenancy, or supported housing, but don't use it, preferring to sleep rough instead. I work with complex needs cases, often the homeless community is their only family and support and they find it very difficult to leave behind. We see it time abd time again, we can provide housing whether it be through the usual homelessness/housing register channels, or by other means, but almost always, the homelessness is only 1 of many issues. Providing housing does not solve all other problems.
Banning the use of tents is not going to help. Access to more support will.