King Daniel Into Darkness wrote:
The entire concept of Trek canon (what's "real" Trek and what isn't) began with Roddenberry's decree that the novels and The Animated Series don't count around the start of The Next Generation. If that's not saying "This is official Star Trek, that isn't" then I don't know what is.
That's not what was proposed, though. The decree was made during the hiatus between Seasons One and Two, and the statement was most often being quoted by Richard Arnold, attempting to answer questions by fans at ST conventions and in "The Communicator", the official newsletter of the Official Fan Club.
Essentially, fans were bringing up continuity clashes between the novels and comics vs TNG and the TOS movies, such as "How can Worf be the first Klingon to serve on a Federation ship when we saw Konom do so, under Kirk, in the DC Comic?"
Of course, TAS had not been available to most viewers in several years
, Filmation was being wound down and sold off in chunks, and the novels and comics are still read by only about 2% of the audience, so why should TNG's writers be forced to comply with every licensed tie-in, which often already clashed with each other anyway?
"That memo" of 1989 was directed at licensees, not fans.