The DCEU fanboys have a big problem with Disney owned Marvel and Lucasfilm movies because the DC ones get bad reviews. That’s why I wasn’t shocked. They also have teamed up with the Bring Back Legends crowd in a weird alliance.
I guess the 90% crap is a bit of hyperbole. Its more like 70-75% crap. For every Thrawn Trilogy or X-Wing book you have Crystal Star or something written by Kevin J Anderson that’s not Tales of the Jedi.