A complaint about the Internet that I see a lot is "You get into a bubble, because you only see the content you've selected, and you only hear from people like yourself. That's how people get so polarized and misinformed." That always sounds plausible to me, until I remember:

Pre-Internet, I used to read a lot of magazines. Rather than randomly picking them off the rack, I usually chose which ones I wanted to read. If they had political content, I picked the ones that were more on my wavelength, not the ones I thought were stupid or evil. (I know some people made a point of reading all kinds of bullshit publications just to have a well-rounded sense of what's out there, but I wasn't one of them, and I think I was the more typical case.) And I was aware that I did not know all about the world just from reading those things; if I wanted to get the full details on things that happened, I would look for a newspaper or an encyclopedia.

Also, when I hung out with people or talked with them on the phone, they were more likely to be friends of mine—rather than enemies, or total strangers in other parts of the country. If a friend of mine started spewing offensive crap, or insisting that I debate them all the time, I probably would end up not talking to them. And I was aware that I did not know everything about what people think just from listening to my friends and acquaintances; if I wanted to know how much support was out there for a politician or whatever, I would look for an opinion poll.

I just don't feel like there was some magic time when people had much broader perspective that they don't now. The pace has definitely changed—it's far easier to get things like conspiracy theories going, just because it's easier to communicate. But being able to read things from my friends list is not the problem.