Word Count Gap

Writing Dwellers has me thinking about word count, or more specifically, the strange gap between novella and novel. When browsing through my own collection of novels I saw that nearly every book I own is over 300 pages long, with some nearly 1000 pages long. I’m not sure what these novels are in word count, but they are probably between 75,000 and 400,000 words. Why don’t I have many short novels?
As far as I know, novellas top out at 40,000 words and novels generally start at about 50,000 words. That leaves us with a strange 10,000-word gap that’s a literary no man’s land. I searched novel length online and I found out that for traditional publication a novel is almost always above 70,000 words. If that’s true, then the realistic gap between novella and novel is 30,000 words. 30,000 words is an entire novella.
What happens to stories between 40,000 and 70,000 words? Do they fall through the cracks? Maybe in today’s market they don’t get published at all. Historically, there were books published in the 40,000-70,000 range that are considered masterpieces, but maybe there is no market for them today. When I think of my reading over the past year, only one recently published book I read was less than 300 pages.
Dwellers will almost certainly be a short novel, falling right into the most unpublishable gap. Where does that leave me? I don’t know.