Your second source merely discusses a New York Times article that talks about how rich people benefit more from social security because they have longer lifespans. It does not suggest that getting rid of the program would help poor people. In fact, it even suggests raising the maximum earnings at which social security taxes are paid or reducing benefits for higher paid workers, which is effectively investing more in the program.
Your first source is much more in-depth but also doesn’t suggest that getting rid of the program would help poor people overall because it is specifically looking at inheritances. It does suggest that social security can worsen intragenerational wealth inequality because it can’t be passed on as inheritance and social security represents the majority of the wealth of poor retirees. Meanwhile, social security represents a small portion of the wealth of wealthy retirees so they are able to pass on more inheritance. Thus, intragenerational wealth inequality is worsened. But there is no indication that inheritances of the poor would be sufficient to replace social security. The paper also notes that other, more important factors contribute to intragenerational wealth inequality and states that wealth inequality would only be reduced to a minor degree without social security.
These sources actually suggest that wealthy people benefit more than poor people and, therefore, the program should be strengthened for the poor. Exactly the opposite of getting rid of it.
Except that, by their own words, removing social security doesn’t solve that problem.