Saying that a system is currently operating below the desired level of performance does not mean that it can't work.
I agree that the USA is not charitable enough, but that doesn't mean charity "doesn't appear to work". The government is also bad at achieving its stated aims, but that doesn't mean we should stop depending on it, or stop trying to improve it.
Or is it that you think even the most charitable nation is not charitable enough? (hence acknowledging that charity doesn't appear to work).
[0] https://www.pewsocialtrends.org/2020/01/09/trends-in-income-...