I don't know that people are any stupider than they ever were. They're probably busier and and are definitely reliant on the convenience of sound bites and talking head summaries and click bait headlines for a lot of their info. Plus all the recirculated conspiracies on email and facebook etc. Who has the time to sort out facts from all the fiction? Just go with what you think sounds good.
When the internet was young it quickly made the world smaller and a bit more empathetic, I think, as regular folks could, for the first time really, have conversations and interactions with other regular folks from all over the world. Wow!
Now you still can but it's not nearly so novel and instead one could argue that facebook, et al, are systems that are more often agents of strengthening ties between small groups of like thinking people, and diminishing ties between those who think differently. (Just delete the jerks from your friend list!) Perhaps it's just plain easier to be divided today, and yet still be part of a group that happily reinforces biases among themselves. That's not the direction I hoped things would go.