No, I don't think somebody getting into Re-Zero is going to start reading VNs like Umineko someday, let alone progress to literature, in the same way as how somebody watching the MCU is unlikely to progress to Infinite Jest.

Geographical distinctions don't really make sense in deciding preference, you start with genre elements and pick from there, regardless if it's Western or Japanese. Ignoring a work because it comes from X country would just be bizarre. As a sci-fi or fantasy fan I don't make distinctions between Japanese or Korean or Western works, nor do I see other fans doing so. For example, I wouldn't be comparing Satoshi Hase's Beatless in the context of "Japanese" works, I'd be comparing it to other AI works. The only limiting factor is translation.

But cross-genre pollination doesn't really happen nowadays, most shounen readers will never go or even avoid mecha, and so forth. Otaku culture especially is much more fragmented today than in the early 2010s.

I agree with your points, but to be honest Bungo Stray Dogs got me interested in Osamu Dasai and Akutagawa...

> No, I don't think somebody getting into Re-Zero is going to start reading VNs like Umineko someday

You realize Umeniko got an anime? Yes, some of the people who watched that anime probably went to read the books, is that really so hard to believe? Authors who got their works animated see a lot more book sales as well. Then as they read those books they might want more so they look for adjacent books, fueling the entire industry.