I believe all novelists should also write short stories. Anthony Burgess had this feeling too, even though he himself largely stopped writing short stories quite early in his career -- there's a piece he wrote about the short story, in "Les Cahiers de la nouvelle" #2, January 1984, that raises a lot of important issues. Burgess subjectively dated “the twilight of the short story as a commercial form” to around 1959 – fifty years ago as I write this blog post. He wrote --
“So if you take the short stories of Joyce and try to read them aloud to an audience which is inured to a different kind of short story, the sort of short story that Roald Dahl now practices, you'll find that the response sometimes is a response of great disappointment. They expect the short story shall contain action, that it shall contain events, shall contain a dénouement, things of change, but all they find in these short stories of Joyce is the possibility of change, the possibility of a new perception, a slight revelation.”
Burgess continued --
“We can only publish the Joycean kind of short story now in a subsidized magazine. The commercialized short story is the short story that people understand and that people regard as a mere truncated form of the novel.”
On the other hand, today the Amazon Sales Rank of Dubliners is #24,719, and that of Tales of the Unexpected #86,989.
My own basic position is that we need the commercial short story as much as we need the literary story, and that unless there's cross-pollination between the the two, neither strain will prosper. For as Polixenes says in “The Winter's Tale” --
“... You see, sweet maid, we marry
A gentler scion to the wildest stock,
And make conceive a bark of baser kind
By bud of nobler race...”
Literary stories are more delectable, but commercial short stories are more vigorous -- for optimal results, genetic material must be exchanged between the two. If the commercial short story ever goes completely extinct, it will be a lot later than twilight for the subsidized short story.