Neither of your points necessarily follows.
They really do. The episode's intended meaning is obvious because the producer has told us what it was. And the mind duel fatally injures the Doctor but only explodes Morbius' brain case; since it would be a funny sort of winning that killed you and not your opponent, it has to be that Morbius has, like he flat-out says, driven the Doctor back to his beginning. You can invent a convoluted alternative explanation, but at some point you're just writing your own episode, aren't you?
Edit: thinking in print here... A better workaround might be that the Doctor is somehow able to cheat at the mind duel, fabricating a false past to keep Morbius going long enough for his brain case to overload. That still leaves the question of how it's possible to cheat at an ancient, well-known mind game, but maybe it's something that's been discovered since Morbius was exiled from Gallifrey. It's still against the production's intention, but I'm not so fussed about that if what happens on screen still makes sense.
Just the sort of in-depth reply I'd expect from someone who's sure of his position.

Seriously, the episode says that there's never been any entity like the Consolation Doctor and that there's never been a Time Lord/human melding like that between the Doctor and Donna. Neither of these is the same as "no Time Lord/human hybrid EVER."
Then there's the fact that the Doctor has consistently said that he's a Time Lord and not a Human
Cause the Doctor is
so naturally honest about his past- just ask Martha!
that he's also said that the thing that made the ConsolationDoctor different from him was that he was part Human
Actually, it was the Consolation Doctor who said "I look like him. I think like him. Same memories, same thoughts, same everything, except I've only got one heart... I'm part human. Specifically, the aging part." So he's biologically human in some ways, which (obviously) the proper Doctor isn't, but this being wacky sci-fi there are still presumably ways for the Doctor to be "half-human" with a human mother without being a one-hearted biological metacrisis product who will age and die. It's all in how you choose to look at these things. Those of us who aren't invested in finding distance between the new and classic series will naturally look at it differently than those who prefer to emphasize the break.

That said, I find it hard to believe that a retcon was explicitly intended, since the episode (and 54 others before it) fail to provide an inescapable one when all it would have taken was a single emphatic line of dialogue.