I don't know what the "tenderloin" refers to, but I guess it is a part of a US city.
That's generally the point I am trying to make. By letting these people suffer from addiction and homelessness, not offering good medical and social care, you are not caring or loving them, which is a kind of cruelty.
FWIW if you search "tenderloin city" the answer appears immediately.
It's a big internet, sometimes people will mention neighborhoods or customs you're unfamiliar with. In my experience, the polite thing is usually to take 3s to make the Google.