> Homelessness and poverty are different issues: although some people might not want to ride with simply poor people, that's a miniscule group compared with those who don't want to be in a confined space with a homeless person who is likely unhygienic, drugged up, or (non-exclusive) mentally unstable.
Homelessness and poverty are related, but you are right in that stigma against the homeless and/or the poor makes a barrier in people's perception of taking mass transit. Some places with robust mass transit have better outcomes than others, so this is something that has to have available options to combat that in culture.
> Saying "free would work much better if there weren't homeless people" is probably true, but that is a pretty big supposition in lots of cities. Those cities without a homeless problem should feel free to experiment with free transit.
I'm not saying its a either or proposition, but making free mass transit needs to be coupled with other actions and policies that also help to deal with homeless by providing more stable shelter, facilities, economic opportunity, etc. Of course, there is no city in the US that does not have a homeless population, so that is always going to be a factor.