Comics and novels have already invalidated the Thrawn Saga with a crappier plotline.
Unless Disney gets desperate to keep fans and starts retconning stuff back into canon.
They ARE putting things back in canon. Not out of desperation but knowing how to work a prolonged story. First you take the tens of thousands of pages OUT so you don’t have drag that albatross around then you say: OK that parts awesome, put it back; and that part; and that one; no not that one. That’s one of the things they’re using SW Rebels for, it’s the big “put it back in canon” engine.
I really don’t get the adulation for that trilogy. While some of the stuff with Thrawn himself was good, the rest of it (a heart-of-gold-smuggler, a conveniently-secret fleet of ships and “Luuke” clones) was painfully mediocre.