In my opinion the way the US deals with homelessness is a disaster because we have a disorganized, disconnected and dysfunctional social net. E.g., how is someone with bipolar disorder or schizophrenia able to treat their condition if they cannot get their medicine because they don't have health insurance? How can they get a home without a job or family support? The list of such issues goes on and on.
Telling people that they just need to have more sympathy and to accept seeing homeless people on the street is a losing strategy and not a solution. In my opinion the solutions include universal healthcare, robust social support systems and drug/alcohol treatment programs. These programs benefit everyone. At the same time it is not crazy to say, "I do not want to see drug addicted people on my doorstep every day."
Perhaps you also agree that these are part of an ideal solution but framing it as sympathy for the homeless is a losing strategy. Everyone would benefit from a social welfare system set up in a sane way, but somehow every discussion in the US turns into an "us-versus-them" mentality. It is like a reality distortion field and a victory of the media-propaganda complex.
Edit: to summarize, homelessness presents two problems, one for the individual experiencing it, and one for society. Solutions need to target both problems. But to deny the reality of one or the other is a critical error.
Do you think the flood of sympathy will then be unleashed, unhindered as it is by the disgusting view of the subjects of the sympathy? No, what will happen is that an issue that almost no one cares about (except, like you, in terms of it being a bother) is further removed from public view.
The chance of people being sympathetic and wanting to help those who suffer is much higher if the homeless people aren't removed from their view.
Inquire within.