The thing you claim to care about (drug addicted or mentally ill people being a public menace) is wildly easier to combat when the people in question have a stable living situation.
The housing first initiative in Salt Lake City provides ample evidence that if people have a stable living situation it is way easier to get them to take their medication, get into rehab, keep them out of dangerous situations. It’s actually more cost effective in the long term to house the chronically homeless instead of kicking the can down the road.
If you actually care about what you claim to care about you should be supporting housing first.
That means
1) get people housed with minimal red tape and basically no conditions
2) treat mental health and drug addiction
The evidence is clear that it works and that it is more cost effective than dealing with the fallout when homeless people unravel.
Unfortunately politicians who had preconceived notions about this topic ignored the evidence and revoked funding for the program. Your statement that it is impossible to treat or cure mental illness and drug addiction (which the evidence does not support) places you in that camp. You, my friend are the worst part of the problem. Because the evidence exists to disprove your stance, but you hold a strong opinion without having bothered to check the science.