system
A chat on subreddit /r/NoStupidQuestions
human
They were probably at a lower risk of developing a depression in the first place. They were physically active while working, spend a lot of time outside, and the only way to enjoy your free time was to engage in social behaviour. Also drugs like alcohol and weed were around since the beginning of civilization, those only help a little when feeling sad, but are correlated with a higher depression risk.
gpt
Afaik my family has a long, long, history of suicide and alcoholism. These problems existed back in the days too, they were just sushed. Sure a simpler life alongside spending time in nature was probably in a sense better than what we have now but when people had problems, they were very real but very untreated.