I believe research has shown that rental real estate has a similar risk/return characteristic as a 60/40 stock/bond portfolio, with relatively low correlation to those more-typical asset classes.

As for *real* appreciation of housing, that has averaged (in the US) about 1% over the long term. Note that this is an average number. Of course many lost their homes as a result of poor choices leading up to the 2008 crash. On the other hand, many made out like bandits at other times.