The fundamental problem with the idea that microtargetting people with different promises is an existential threat to democracy, I think, is that people tend to

The fundamental problem with the idea that microtargetting people with different promises is an existential threat to democracy, I think, is that people tend to compare with their friends and notice this and that it makes for a really juicy viral news story when they do because people do not like finding out they've been tricked. Also, as far as anyone can tell Trump's campaign didn't actually do it - they tuned their message based on feedback from monitoring the response to it and carefully targetted who they paid money to promote it to, but everyone got the same message.