Hierarchy is simply a reality. Believing in hierarchy is like believing in reality itself (i.e. someone is going to be better than me at weaving baskets voilà you have a hierarchy: simple as).
That's not exactly what was meant by hierarchy. It's more like having some people rule over others is good and natural. And that people don't really change their station in life. You're a peasant so course the royal family rules over you. They're good at ruling. Perhaps innately.
There is no obvious limit to what can be considered “charity.” So, if the government takes responsibility for providing charity instead of leaving it to individuals and communities, it can use that as a reason to keep expanding its power and responsibilities.
I don't find this a compelling argument. "Something bad might happen so we shouldn't do anything". I'm sure many of the people suffering from lack of food, shelter, and health care also do not find it compelling. You shouldn't go outside because bad things can happen there. You shouldn't lend your phone to your friend because there's no obvious limit what they can do with it. You can use this argument to avoid anything.
The appeal to the "founding fathers" is not very effective. They lived a very long time ago in a very different world, and were not saints.
Maybe they should instead build technology that people want and that solves their needs.