The key is to buy when everyone is dunking on you calling you an idiot. Then you 3x your money in a year or two and sell when they start asking you if it's too late. Rinse repeat. (yes I'm in on it.)
Bear in mind that 1) just because millionaires own real estate does not mean that they became millionaires BECAUSE OF real estate and 2) real estate can offer better gains because typically it is leveraged and/or because you have to manage it (moreso than equities anyway).