In Disney canon Palpatine specifically made sure to spread as much propaganda about the jedi as possible on top of deleting nearly 100% of their records. So the people who were kids and/or born during that time had zero exposure to what the jedi order was like.
Yup. One of the few things I liked about the Force Collector book is that kids even in the ST era either don't believe that the Jedi were even real (which fits somewhat with Rey in TFA) or buy into the old Imperial propaganda that they were all traitors.