The main argument of capitalists is that government intervention always makes things worse.
They follow premise:
P1. Government interventing to help poor people will not help poor people, but will harm poor people.
Now, while its true that historically, there were countries with very little government intervention, most of the rich countries today have lots of wealth redistribution.
Thus, capitalists would have to defend position that countries with most free market have least poverty.
This position is very hard to defend, because
1. Countries with least poverty are countries that have lots of government intervention.
2. There is no country on Earth without wealth redistribution
Also, they would have to defend that capitalism on its own wont produce the effect of wealth moving up.
Because wealthy people would have much more wealth without high taxes, it follows that their buying power would increase. Thus, they would consume more products from market, and market would increase production for the wealthy while reducing production for the less wealthy.
Since in capitalism, the richer you are, the easier you can compete and more you can consume, there is basically no guarantee that making rich richer helps the poor.
Capitalists would argue that:
P1. Not helping the poor motivates poor people to get a job.
While it is undeniable that poor, if being left on their own, would be forced to die or find a way to survive on their own, this doesnt result in much good. First, the job they might get would likely be the lowest wage job. They would likely have no money for health service, leaving them in very vunerable position if they get sick.
Second, the unemployment rate in countries with lots of wealth redistribution is very low.
Third, poor people having access to health services payed by government ultimately makes them more productive, where without health services their health would decay and force them out of workforce.
