It does have an auto save that can rescue you from a crash. Tools > Options > General. I think it defaults for every 10 minutes, you can change it to less. If the program crashes, you can restore from the auto saved file.
Autosave doesn't save you from yourself though. I think we've all done what you did at one point or another. I don't think I would be a proponent of auto saving like youre requesting, I sometimes go in and make changes just to see what would happen, I do not want those changes to save, so am careful to choose NO upon exit.