Following your logic and example, since we can't individually do much for the homeless we should go around shelters and aggressively try to convince volunteers that destitute people are a lost cause.

Bullshit take a blanket and a old jacket and sit down with a homeless person, it absolutely could have a huge impact on them.

Even if you are in need you can still help. I volunteer at a food bank every Wednesday. It is ~2 hours of my time. I also am able to take about as much food with me as I can carry. Most of the food I take I then give away to the unhoused that live in and around the park across the street from work.

I used to volunteer at a church doing food bank stuff too.

There are plenty of things you can do while you are the one in need.