She has the money to save the lives of tens, if not hundreds of thousands of people through helping them out of poverty, funding food and medical care etc etc

A person deliberately choosing higher numbers in bank and stock accounts over this is a horrible person. Less horrible than actively harming and abusing similar amounts of people but nonetheless horrible. After all, if you see someone hurting and/or dying and make no attempt to aid (provided you have the means to do so), you are nearly the polar opposite of okay.