What do you do though if a small but vocal subset of a population truly believes something that everybody else thinks is fake is actually real, it could either be a disenfranchised minority or a hyper nationalistic group.

Even though I've worked in ML professionally for many years, I still feel like fake news is a social problem akin to identifying the difference between propaganda and news and I'm not really sure how this is a problem technology can solve. It's just an old hard problem and akin to a solution against fascism and class struggles.