The more I post about this stuff, the more I feel like a broken record and yet, I feel it's truly worth mentioning just how far indie books are going in recent years.
Recently, Rob J. Hayes of Best Laid Plans fame got picked up for a Warhammer 40k short, and his latest book Herald is being represented by the John Jarrold literary agency. SPFBO finalist Devin Madson is being represented by literary agent Julie Crisp. Both are fantastic authors and I highly recommend their work and wish them the best with their trad books.
This isn't to suggest that indie books aren't "real books" until picked up by trad publishers, however. Rather, it shows just how influential the indie market is in genre lit, to the point where major sellers in the space occasionally cross over into the ivory castle of traditional publishing. There are of course, great authors like Chris Fox, Will Wight, Daniel Arenson, Andrew Rowe and Bryce Connors, who all sell amazing numbers (like, hundreds of dollars per day on one book numbers) and work just fine in indie. In fact, they're doing better than most midlisters and on par or better than some trad bestsellers.
In my recent interview with SPFBO '18 finalist Steven Mckinnon, I briefly touched upon the growing influence of Eastern European, Chinese and Japanese webnovels and fantasy fiction. Stuff like LitRPG and the Witcher series. Isekai novels like Re:Zero, Shield Hero and Overlord. Xianxia and Progression novels from Taiwan and China. And while I'm not saying that the western fantasy lit market is 100% influenced by foreign works, it's hard not to see the creeping influence of games, webnovels and anime, even in major releases like Kings of the Wyld. It's not just thematically either, as I see growing parallels between foreign book publishers who often pick up webnovels, and our own Amazon indies turned trad writers. If this continues being a trend, it's entirely possible some of these indie books could end up as streaming shows or even animated features here in the US. Given how fantasy TV series seem to be in high production demand right now, it's not entirely out of the question that Sufficiently Advanced Magic ends up on Netflix.
The latter is of course, just spitballing. Indie or trad, publishing's a volatile industry, so it's hard to say exactly where things go from here. Despite this, I'm certain that as long as people are making cool stories and indie IPs, cool stuff will follow in some form or another.