They haven't though?
There was only a brief period in the nineties when TAS was in limbo, being left out of certain official publications. But even the writers of then-current shows referenced it.
It's been fully back in the official continuity since the mid-2000s.
At a minimum, Lower Decks is dragging all of its TAS references into continuity, many of which are actual plot points, and Lower Decks is holding hands with Strange New Worlds.
