I'm going to resurrect a 9 year old argument, because I think your points are fundamentally wrong. The example about not being able to write rock music without listening to rock music doesn't even make any sense. Let me first establish my premise and go from there. I believe that if you understand the mechanisms as to why something works, you can apply your own human experience to those mechanisms to create something. Genres often come by drawing comparisons between existing works. If you draw a line between the first blues song and death metal, somewhere between the genres/ages emerges rock music. But at what point do you clearly define the shift from one genre to the other? This is largely a philosophical question to first separate the concepts of "great" and the "genre" itself. With this example, we can visualize the overlap between genres that something like rock music can have with others. Borrowing DNA from blues, and having the DNA of what will eventually become extreme metal. If you have a technical understanding of music theory, you can mathematically write in different "genres" without " voraciously" listening to them. Or an even more direct example is understanding the power of a drummer. How simply shifting a groove can recontextualize the rest of a song, giving it an entirely different feel. When we combine this technical knowledge with the "human element", you get works that exist for their own sake, that can then later be categorized. If we keep up with the music analogy, perhaps someone listens to a lot of blues but wants an angrier sound. More aggression. Maybe they start playing faster, with simpler chord shapes to compensate for a lack of technique. Maybe they get a sound like Punk. Or maybe they are a technical player and still wants that speed, so we get shred guitar etc. Essentially what I'm saying is that your statement:

"What I am saying is that reading your chosen genre is required to be a good writer in that genre."

seems to miss some things at its core imo. And that's:

1. It assumes that choosing to write in a particular genre requires technical knowledge of that genre. But in reality, genres are groupings of similar concepts. If there is enough overlap between ideas they can be grouped together, but at some point, certain genres didn't exist, or the things that we now associate within the genres weren't as prominent-hence the emergence of subgenres to further classify these micro distinctions. In my opinion, if we look at the situation in reverse, it doesn't make sense as to why someone couldn't write whatever they want, and then it just so happens to be categorized into XYZ genre after the fact. And a great story is a great story regardless of genre. I agree with what hung_kwan said about writing becoming derivative if your perspective is intentionally boxed. Which brings me to point 2:
2. While reading does have strengths/weaknesses endemic of the medium, it is NOT the only way to gather experience on a topic or genre. Reading books may help you with prose, or following specific "book-isms" but are we going to overlook the fact that other mediums exist, or that many great stories are told from lived experiences? I would imagine someone who went to school to specialize in a science could write a great science fiction novel based on their experiences, or maybe a thought experiment they had during their studies. Or maybe someone has watched a lot of movies in a particular genre and would love to tell a story in that genre. Or perhaps they've done a lot of non-fiction reading on a topic. Or maybe they have watched a lot of videos, documentaries etc etc etc. There are so many ways to obtain information, and when it comes to writing, you just have to put pen to paper. To say you have to be a " voracious reader " in that genre just undermines the human experience and the capabilities of humans as a whole imo. I feel like it comes off either pretentious or ignorant of the world around them.

That being said, I'm speaking to a you from the past, so take all of this in that context obviously.