On the whole, I think people's happiness depends on those people, rather than their material circumstances. After all, there's only so miserable you can get (or so cheerful). Most people are wealthier; but even very wealthy people evidently think they don't have enough money.

I don't mean to suggest that miserable circumstances don't make you miserable; just that circumstances that are twice as awful don't seem to make people twice as miserable. I suspect that most mediaeval peasants were about as cheerful as most ordinary people today.