You've mentioned "Correia getting published" a few times as evidence that there has not been a narrowing, but this fact doesn't support your claim. The fact that one thing X exists does not demonstrate a lack of structural barriers to thing X existing.
I think this is a great point. I've been a fan of Larry's since I read the first sentence of his first book ("On one otherwise normal Tuesday evening I had the chance to live the American dream. I was able to throw my incompetent jackass of a boss from a fourteenth-story window.") I've been reading him ever since.
Larry came into the industry as a self-published author, and even though he's been picked up and sells tons of books, he is very much on the outside of mainstream Sci-Fi/Fantasy/Horror publishing. The whole point of Sad Puppies, which was over 10 years ago, was to highlight these differences.
In the case of the Hugo's, when I was reading the most (in the 80s, when I was in school and had the time) I read just about every book that was even nominated. I remember going to the library to pick up a list of Hugo Award winners so I could read past years. I typically have only heard of one or two of them now. And it's not like I'm just reading pulp, popular literature. I'm an English major, and I try to stay in touch with the book world, but what's awarded in the Hugo's is not what I'm interested in reading.
And I feel it's important to say this:
that's fine. I'm 100% not trying to yuck anyone's yums here. The problem I see is that new authors getting into writing have problems getting noticed. That's only one of many problems these days, where if you're writing a multi-book series, it's hard to get published or get traction because so many people expect the series to not get finished.
I think, much like the Oscars, there has been an issue with what's
awarded versus what's
read or
watched. And with publishing houses that are risk averse, that's a problem. Put that together with political issues where authors that get read find it hard to get into book stores, and this is a problem. It's a problem for me, I suppose. If you don't like Larry's books (or similar authors) I would not expect you to care. I do care because I want to see lots of books by lots of authors with different perspectives. Even if I'm not going to read a lot of them.