Contrary to (apparently) popular opinion, index funds are not people.
This is such a weird response because nothing about index fund inclusion rules has anything to do with whether or not a fund is a person.
Complete non sequitur. Can you explain what you mean? Did you accidentally reply to the wrong comment?
No, they're just owned by people. Most of whom aren't billionaires.
Correct. Index funds are owned by people. For example, I have invested a large chunk of my retirement savings in an S&P 500 indexed fund (as many, many other people do). Whatever stocks the S&P 500 list, are what I end up owning; if I don't want to own one of those, I have to either roll that money into a different fund (which IIRC has limits, can't do that too often without tax consequences) or take the money out (and pay a tax penalty for withdrawing it before retirement).
So whether the index funds do or don't buy a certain stock has direct implications for real, non-millionaire, people.