Yes and no - the idea of insulating existed 100 years ago, but the materials weren't the greatest (attics full of horsehair, etc.). And the cheapness of fossil fuels made it seem mostly unnecessary. Moving from a drafty 1921 home to a passive house that was built this year, the difference for me was striking. Some of the improvements can be retrofitted onto older homes (PV, blown-in insulation, attic insulation), others, not so much (windows and doors are more painful to replace, e.g.).
Sure, windows and doors are more difficult to replace, but it's all quite doable, which is striking considering the century that passed in the meantime. It's a testament to how slowly housing technology evolves.
Old homes may have assumed cheap heating, but new homes seem to assume AC (cheap electricity). I have comfortably lived in 100-150 year old row homes without AC, and have sweltered in a 25 year old row home with broken AC in the same city during comparable summers.
Those drafts are a godsend in the summer, homes without drafts or AC turn into solar ovens.
(Other properties of old homes, like high ceilings, also contribute to livability in the summer (at the expense of being more expensive to heat during the winter))
So basically you have a seemingly balanced tradeoff; do you want to waste energy in the summer, or in the winter? Of course the tradeoff is not really balanced, you can put on more clothing in the winter so long as you keep your home above 0C (for the pipes), but you can only take off so much clothing in the summer.
Opened windows along with box fans (or better yet, a house fan: http://en.wikipedia.org/wiki/Whole-house_fan) will help, but you will still be in a worse situation than if you had a house designed to stay cool and the same fans.
Houses designed to stay cool without AC, among other things, tend to have more intelligent window placement, and windows that open much wider than is perhaps normal (you won't find those rubbish casement windows that only crank open to an acute angle in homes designed to stay cool without AC: http://www.choicesil.com/images/House1-16-08%20017.jpg).
Given the option of staying in a house that never had AC, or a house with broken AC, I would chose the former every time. Fans and open windows will help in either case, but they will be more effective in the home that prioritized that usecase.
