They can objectively afford less housing, education, healthcare and such things than 40 years ago. They can afford better computers, but that is just thanks to technology, other than technology making things cheaper their lives are worse.
"Education, healthcare" ... depends on the country involved, plus the extent of healthcare you can now get is vastly bigger due to scientific progress. Forty years ago, HIV infection was a death sentence and most cancers too.
It would be impossible to house homeless in vacant houses. Sellers and landlords would never accept it because would make it hard to find people. The short-term rentals would be hard to mange, not good for the homeless to always be moving, and easily go wrong. Is the government going to compensate for damages? For delayed moving into new house? It is almost certainly cheaper to build the homeless housing.