|He was having a laugh|
There are several possible explanations for this divergence of opinion, but the more dignified one, for everyone concerned, is offered by Einstein’s observation that any Mensch is only capable of fully comprehending a single philosophy in his/her lifetime.
And possibly there is a parallel situation in art. Perhaps we are only capable of fully appreciating one style, ambiance, mode. If someone’s predilection is gloom, then no matter how much they find themselves laughing at a comedy, deep down they’ll still hanker for misery instead. In HW-R, HP jettisons his overwrought obsessions and writes narrative for its own sake. There’s a sense of liberation detectable from the rollicking sense of fun the stories display -- the very quality glaringly absent from his other stories. No doubt about it, HP took his work far too seriously (he disliked HW-R) and the critics referred to on Wiki clearly take HP as seriously as he took himself.
One might posit that it is a mistake to take any artist as seriously as he/she takes themselves. On the other hand, I may simply be missing something. It could be that my taste is defective and the part of my brain that should tremble in harmony with the portentous, the melancholic and the profoundly disturbing isn’t in situ.