I really loved the first book when it hit during college for me. Shades of Harry Potter esque magic school adventures mixed in with a cool frame story twist, lots of cool intimated backstory hooks, an interesting magic system (at a time when I was still “into” interesting magic systems), and–and to be clear, for much the same reasons as you, re: Martin and Jordan, this was genuinely important to me–an author who said he’d already finished the trilogy after a decade of work at grad school and would just be able to put finishing touches on books 2 and 3 before releasing them.
Four years later when book 2 came out, obviously the shine had come off the latter point (and even moreso 7 years hence with no sign of book 3 on the horizon). But moreover, in book 2, the story spun around in a handful of locales without seeming to move forward much. The dopey Gary Sue esque love storylines from book 1 came back in far more, erm, explicit and trying forms, while a lot of the stuff I liked, like the magic school, was getting pushed to the back burner. The frame story sputtered and halted. And by the end of the book, I felt like almost none of the interesting questions from the first book had been answered while the plot had advanced very little, all of which made me even less interested in the new questions this book raised.
Moreover, it felt like, based on the bits and pieces of the MC’s later life we have gathered through clues, the “main story” wasn’t anywhere close to a conclusion, which probably meant one of two things for book 3: it would either need to rush through a lot of seemingly cool moments in order to reach the conclusions we knew it must, or that this trilogy was about to turn into a quadrilogy or worse. (To be fair to Rothfuss, there’s also strong textual evidence that this winds up being very much not a prototypical fantasy coming of age story and all the Bildungsroman building block puzzle boxes he’s laid out are a wildly elaborate series of red herrings that disguise his goal of turning the model on its head and giving us a very different conclusion than what I’d–personally, of course–enjoy at all)
In the intervening near-decade, the author’s highly public presence combined with seemingly interminable progress on the novel took on Martin-esque levels of absurdity, especially when he’d occasionally lash out at fans over the inevitable questions that would raise. Watching him fritter away time on RPG projects, novellas, cons, and his (admittedly very cool) charity side project via his blog while the book deadlines slipped further and further turned frustration into outright anger for a lot of folks, self included.
When I’d finished book 2, I was very annoyed by parts of it, but still mostly onboard with the Rothfuss train, hopeful it would go somewhere good (and still enamored of his writing, which I think is very lovely in a way mainstream fantasy rarely achieves). In all the years since, I can’t say my opinion has improved at all.