I've been on the 'internet' since 1981. I have never seen this mythical beast of nostalgia that is an internet without assholes. Hell the first times I got engaged in internet slap fights was over uunet and fido relays. Trolls built the communities on Usenet, trolls drove the traffic, and once ina while there was an amazing conversation with someone a thousand miles away that made it all worth sticking around for a bit.
The people on the Internet are just that: People. People are smart, funny, amazing and wonderful while at the same time being frustrating, stupid, assholes and trolls. People need to learn how to deal the bad so they can participate in the good.
I actually found this to be fairly nuanced review. It seems to be more about our evolving relationship to the Internet, how it fits into our "real lives", rather than about a mythical time without assholes. There have always been assholes online, that's true, and it's mentioned in the review. The review/movie seems to be saying that the Internet was once a refuge from real life because it was removed from it, but now our personas are so entwined with the Internet, through things like Facebook, that the feeling of refuge is gone. When you would encounter a troll early in the history of the Internet, that had minimal impact on your actual life because no one knew who you were. Now things are much more "real" online because the line between your online and "real life" self has become blurred, if not obliterated.
I was born in Rio de Janeiro state in Brazil. The people from my state are usually fun and friendly people to hang around. They enjoy a conversation and having a good time, really approachable. Until you talk to any of them on the phone.
After I moved to São Paulo, one of my first jobs was on a call center doing tech support for one of the countries largest ISPs at the time. This is when I learned to loath the people from my own state. Once they're on a situation without face to face contact or the possibility of being smacked, they turn into the biggest assholes around. Impolite, arrogant and stupid assholes. Specially when they believe it's their money that pays your wages (hint, it was not. 2 million costumers paying 40 buck a month, each one contributed fraction of a penny to my wages).
Fact is, unless people are educated (I would even say "indoctrinated") from an early age to be polite and respectful even when not in presence of the interlocutor, people turn into beasts, simply because they can (i.e. there will be no consequences).
Someone should do a research (if they haven't already) on humans ability to empathize while separated from others. The results would explain pretty well why internet trolls act like they do.