It is directly related to the index funds. They are now marketed as the "correct" way of invest into the market where they in fact invest into a very small numb

It is directly related to the index funds. They are now marketed as the "correct" way of invest into the market where they in fact invest into a very small number of companies creating an artificial wave of the buy orders. Actively managed funds have choices in what they invest, and how much they put into any of the companies. Index funds do not. https://www.etf.com/SPY#overview https://www.etf.com/SPY#overview for an example.