That schizophrenic meth addict deserves help as much as anyone else does. Drug addicts don't become drug addicts just because we can: and mental health disorders are pretty much always comorbid with addiction.
And I'm not saying that they're not. But the reality is that that help isn't coming from the average person on the street. The institutions capable of actually providing help, already have access to this data.
What's relevant is the proposed tech empowers the average person the street to quickly access and synthesize already public information. It's essentially no different than a real-time background check.
And I would almost certainly think that you'd agree that in a situation where your personal safety is potentially at risk, that you'd prefer to have this information available to you. If you were hiring a baby-sitter for your kid, would you not conduct a background check. If the background check revealed that said babysitter was a schizophrenic meth addict, would you still hire that person?
Of course not. That person needs help, but you as a private individual going about your life is not the entity capable of providing it.
You're arguing something that I never said, though. I agree with you: private individuals should not be expected to fix systemic issues on their own. But the government and the institutions and so on that we create sure should.
They deserve sympathy, but not necessarily the same care. For maximum societal benefit it may be that it's better to spend more on kids in school than schizophrenic meth addicts. We live in a world of scarcity, we can't do everything.
But if the original complaint is the implied threat of violence from said homeless addict, especially aimed at those kids in school, you can see why I find that a bit heartless.
Besides, the school system needs more than just money, just like the "homeless problem". I don't feel comfortable passing judgement on one class of people vs another solely because of the circumstances they were born into.
I absolutely agree with not passing a judgment on a class of people because of variability of how they respond to help. I've never heard of any reason that all 'schizophrenic meth addicts' as in GP's example will not respond well to help. If hypothetically they all show no positive outcome from the help they have received, then it is indeed fine to say helping them this way is a waste of time and resources, until a new method of helping is devised.
The part 'vs another solely because of the circumstances they were born into' from the parent post does not reflect what the GP post actually says. The GP was solely arguing on the practicality and the costs and benefits of doing it; solutions to problems have trade-offs, it is no good wishing them away.
That said, how the homeless are treated in a lot of rich nations today are a complete disgrace. Increasing a well off persons well being is worth far less than increasing a not so well off persons well being IMO.