People should just go back to forums. It was better when I didn't know about the absolute nutcases and always felt like forum information was superior to the stuff I find on Reddit.
So "brigading" and such weren't really much of an issue (and the issue has always been people barging into a community, knowing nothing about it, pontificating on some post/issue, and promptly leaving).
Forums still exist, but you need a slightly strange sort of person to continue to put the effort into them when Reddit is "free and easy".
Reddit is easier because you already have an account, but creating an account on a random site has never been easier to do or manage, so it's not that much harder (and importantly, people already do it because not everything is on reddit so it's not "new" to learn how to create an account somewhere).