You have some common misconceptions, allow me to teach you something new.
- I know a great many PhDs who are Objectivists (hopefully myself soon, too). It's really not a philosophy for teenagers and that is just something people spread to put it down without using a real argument.
- Objectivism can deal with children and family just fine. Lots of Objectivists have children and families, including Ayn Rand's closest philosophical associate, Leonard Peikoff.
- Objectivism does not say that wealth creation is the only goal. It says (summarizing) that self-preservation is the root of all values, and experiencing your values (in myriad ways) produces enjoyment. Wealth creation is just one way to experience your values, not the only way. Another way is, for example, through family. There are lots of Objectivists who choose non-lucrative career paths.
A society is to be judged by how well it treats those who are worst off. Optimize for that. Not the average, the median or the mode.
Prove it formally.
I can formally prove that it's not, so I'm just saying this to get you to think about what that would entail and reflect on how supportable your claim is.
There is one social model that has been truly successful in human history and has truly brought unlimited masses out of the darkness and into the light, and it is not based on altruism. It is based on (a) rule of law, not of men and (b) individual rights, especially property rights.
The Gates would do well to start preaching this model instead of the one that has failed over and over and over all throughout history, which is: you have a duty to be your brother's keeper (altruism).