The world has always been a complex place, but we manage that by many layers of abstraction, mostly innate but also by social organization.
The failures of social organization and complex coordination are genuine, but they're not occurring because our world is much more complex. I have a speculation on the cause which can be convincingly demonstrated but it's the species of topic where HN is liable to change the colour of your text in its lalalalalalala-itsnothappening-mode.
Under most lights our world is more simple than it used to be. You didn't have to fetch a pail of water from the well this morning. Your clothes: washed, possibly dried by machines in a process that used to take a day out of every week. Your food... you see the picture. Getting blitzed by streams of information on the internet isn't the same thing as the world becoming more complex, that's partly a choice and something people used to do with a library card - besides most of the web is not especially information dense and that's another illusion. When we do a lot of the human version of context switching it doesn't take much to overwhelm our sense of proportion.