Bedrockgames
I post in the voice of Christopher Walken
Keep in mind, the two things I am saying he may be coming to terms with internally are the possibility that he has inherited mental illness from his mother and his father, and perhaps a growing realization that he isn't physically well. I don't know that a writer writing a story like this and using that as fuel to make the sort of ending this story has is giving him a lot of credit. That is pretty much how writers function in my view. I'm also not saying this is fully conscious. I think there are other things going on the story, which again I don't think we can really get into.I think you are giving HPL way too much credit here, but I guess there is no harm in that. Like you, I don't want to discount the role of the reader in the communication either, least of all in rejecting the writer's take even once and especially once you understand it.
For me though your take is tying back into my problem with attempting to scare modern readers with horror, in as much that even forced transformation and loss of humanity and an alien conspiracy that amounts to a cuckoo breeding strategy makes you shrug and go, "Isn't it pretty! Look, he's coping with his mental illness by accepting his inner nature!"
Well, I can see what you are saying, but I don't think that moment of beauty at all undermines the horror for the reader because there is still something very uneasy about that too. When I first read it when I was in highschool the beauty of it was something I completely missed for example, and it wasn't until later that it became more clear that there was beauty there and a kind of religious language. But even then, that is still an odd thing to feel after all the horrors leading up to that. To me that is a very Clive Barker thing, and I think he is very good at making horror that is both beautiful, even morally a lot more cloudy and unclear, while still frightening me as a reader. I suppose everyone is going to have different tastes though in terms of what they find scary. There is a point where you can go too far with things like beauty, comedy, romance, in a horror story and it stops being scary (but there is also a sweet spot where those things can enhance the horror).
Also I am not saying one should take all alien horror and make it beautiful or misunderstood. I don't think that would add anything to the Xenomorphs for example (it might be an interesting political or social commentary but it wouldn't be especially scary I think). So I do take your point. Here though, this is more like a puzzling final passage in the story that makes me question everything I've read to that point.