I’ve started to learn about options, but for now I’m staying with long term stock investment. Maybe I’m not understanding the language, but I thought RH and eT

I’ve started to learn about options, but for now I’m staying with long term stock investment. Maybe I’m not understanding the language, but I thought RH and eToro and the like made money through enabling high frequency trading against their customers. My guess/intuition is that this would increase volatility but reduce the expected returns of their users when compared to trading stocks through a broker. Am I terribly lost here?