Some technologies actually have had unintended side effects, but not always the ones we saw coming. Artificial lights are killing all the insects which nobody really worried about and cars do kill tons of people, which we worried about in the 1920s. I don’t know what the deal was with leaded gasoline, that one was just bizarre.
All in all, it’s just really hard to anticipate how society and technology will interact. We think about the environment now but I don’t know if any systematic progress has been made on predicting the human factor.
screened windows (society will collapse because you won’t hear your neighbours and pedestrians on the street, we’ll all become hermits and die holed up in our homes)
This one has actually come true to a certain measurable degree (see Bowling Alone, written at what is now the midpoint of the trend), but I don’t think it’s down to window screens.