> Otherwise these few companies are the largest holders of basically every security in existence.
Indeed. Due to inclusion of Intel in S&P500 index funds and ETFs.
Together, institutional investors own over 50% of Intel Corporation, giving them a significant collective influence on major board decisions. https://finance.yahoo.com/news/67-institutional-ownership-in...
A company can own lots of things (assets, IP, real estate, share of other companies), but shareholders of the company don't own or have direct access to that thing. If Intel pays dividends, it will go to Nvidia, not you. If Intel holds a shareholder vote, Nvidia leadership will be the one voting, and they don't have to listen to your opinion. They can also change or sell the holding without your permission.
If you own shares of Intel through a Vanguard fund, you do have actual ownership of Intel. You can cast a vote same as every other shareholder. The dividend they issue will be passed on to you. Vanguard is simply acting as a proxy.
So I generally think wha is more useful is saying in what particular ways “individual investor” is meant when it is used in debate, decision-making, etc.
The individual human called Citizens United is casting a side eye.