Matters of taste, etc. I happen to like alliterative verse, the little bit I've read in translation that was rendered in that style and I'm reacting to seeing a rare modern take on it.

I know it's a weak defense to state that I purposely didn't quote from the ends of the cantos but the beginning points, but there is that as well. There is, for me at least, a crescendo effect. What I quoted barely hints at that, I'll grant and in isolation, some might feel a bit "off." But I could argue that some of the same applies to works that are even more accomplished in terms of achieving a certain style:

Much as I love this epic (it is one of my 2-3 favorite pieces of literature; I quote an English translation for those who don't read Italian), if one is disinclined to the octave style of Ariosto, then the descriptions and poetic metaphors will sound like the braying of a drunken ass.

Of course, this risks setting up a circular argument regarding the evaluation of verse and I do not care to go that far down the rabbit hole, so I'll just have to center this too-lengthy apologia around the matters of taste argument and argue that to my internal "ears," the sounding out of Tolkien's verses sounds excellent to me, as there is an odd yet strangely familiar rhythm to it. Add to it my love for the Matter of Britain (the "Matters" being my primary literary love of my adolescence and early adulthood) and seeing an Arthur that is recast in a far less "romantic" fashion than those works of the late medieval and early modern periods and it makes sense for me to be drawn to this work.

I thought it sounded more like something that I would have read from an edda than from Tennyson, but I'll grant that it's been over 15 years since I last read him.

I suspect it's very close to happening. I will note that his essays, which comprise over 3/4 of the book, are nigh useless for those who already are aware of the subject matter.