Not really decadent enough for my tastes, though the ontological horror at the end is almost enough of a pay off.
I can imagine folks complaining about Machen’s inability to vary his tone. All his characters sound the same (so no wonder virtually everyone’s of the same class of Drones). For example, here are two characters talking:
“I was wide awake enough. Even if I had been dreaming as you say, what I saw would have roused me effectually.”
“What you saw? What did you see? Was there anything strange about Crashaw? But I can’t believe it; it is impossible.”
We might say that Machen’s displayed the smooth workings of this world of humans, beyond which lies the horror of Pan’s world, where we have, for example, “the hideous form upon the bed, changing and melting before your eyes from woman to man, from man to beast, and from beast to worse than beast.” In other words, the very blandness and sameness of the dialog, the indistinguishability of the characters, perfectly represents the world’s unvarying and proper order. Change itself, then, is Machen’s great horror.