Have you ever had the perception passive investments in general (stocks, real estate funds...) generate a very low profit margin?
It stays around 0,6% monthly profit, what means you need 100,000$ invested in order to generate 600$ bucks a month.
Investment of this kind is not attractive but still many go through this because they perceive it to be a safe investment, safe investment has low profitability, just like in a bank you put your money into the bank for 2 to 4% annual profit and if the banks loaned that money to companies they charge 6 to 8% or even more.
That's because they take risks, risks investment whether medium or high risks give the most profit potential,
Passive investment is part of a diversification of the portfolio, you have a high-risk investment and you have a low-risk-passive investment, passive investment is what will sustain other ventures if the investor finds one, so they keep low-risk passive investment for future mobilization.