Tax planning can help here. By converting the house to ownership by a tax-advantaged trust , a family absolutely can continue to extract rent from a former property without selling. Doubly so if the mortgage is paid off.
Sure, that can help affluent families in some cases. But many elderly people will be forced to sell (or reverse mortgage) their real estate holdings in order to pay for long-term care. Fees at decent assisted living facilities are often in the $8K per month range now so the only way to afford it is to sell the family home.