Do you know many people impoverished in their old age because they bought a couple of houses (assuming no mortgages)? Bank savings inflate away, stocks crash, houses are typically as safe as houses.
Houses cost property taxes, insurance, and maintenance. Those have been known to force seniors out of their homes.
The canonical problem isn’t “a couple of houses as part of a diversified portfolio”. It’s “entire net worth is effectively tied up in one house”. We saw what happened with this 10 years ago. Houses are only reasonable stores of value if there is some scarcity attached to the particular house.
property markets still collapse. Towns turn into ghost towns, it’s not bulletproof. The absolute safest thing is cash in a bank. It’s an absolutely terrible investment, and you’d be an idiot to do it, but it’s safe.