Yep, if you've got channelers it's never going to be an out and out medieval equivalent. In some ways the books are also quasimodern- doesn't seem to be much if any illiteracy for example, when maybe 5% of a renaissance society would be literate. But, in most ways and for most people there was very little difference between medieval and renaissance anyway- more or less subsistence agriculture, horse power, horse or water transport, very low education etc.
I guess, technically, it's most accurately described as a post apocalyptic society and if you want to get really technical, post apoc twice over.
Yeah, it misses the feel except at very occasional points. It also doesn't feel consistent in what it does do- as simple as each person from the same small isolated village having a different accent. I'm sure half the complaints about it looking like cosplay is because of the lack of consistency in anything else, so far as I can tell the costuming is objectively fine. There's no sense of scale. Things are rushed, other things have too much time spent on them. And there's just enough good stuff there (put an example into the spoilers) to make me more disappointed with the stuff that doesn't work.