This series has really gone downhill. Series 6 was pretty damn good all things considered because there was enough detail etc. but the filler was being debrided. Good, said I. Filler is GRRM's biggest failing. Nobody gives a shit what people are wearing or what they're eating or suchlike.
But the last series and this one has felt almost as if they're just phoning it in. The big fucking Deux Ex Machina of Arya coming out of nowhere and stabbing the Night King in the gut, who just so happens to be a load bearing boss. I might watch the next two episodes but I've felt, not to put too fine a point on it, underwhelmed.
I think the root problem is that GRRM has never known himself what the ending should be or how to get there. Considering the lather he got himself into over the Meereeneese Knot when writing A Dance with Dragons, and considering that the series expanded from a trilogy to a heptalogy halfway through writing A Clash of Kings, I can't say I'm surprised.
The X Files had this problem. They kept adding layer upon layer of fluff and twists and developments and false endings and it just collapsed under its own weight. Ditto Lost.
Coincidentally, Breaking Bad didn't. Why? Because they knew what they wanted to accomplish and worked out how to get there in advance. They also knew to quit while they were ahead.
In literary terms, The Wheel of Time had this exact same problem with trying to write a 14-volume epic and not knowing how it ended properly. It got to the point at which one of the books, Crossroads of Twilight I think it was, had as its big bad, fucking GRAIN WEEVILS. And then the author died.
If I were GRRM, in The Winds of Winter, I'd have the Others come over the Wall, murder everyone, and subsequent heat death of the universe. The end. And the last 100 pages would be filled with trollface. Torch the franchise and run.