Are Great Sight-Readers Born or Made?

In the age-old debate about nature vs. nurture, I know the correct answer for most things is that it's a blend of both.But sight-reading, at least for me, always felt like one of those things which leaned more on the nature side than nurture. Some folks just seem to have a knack for it, while I always struggled.But what does the research say? Could I have gotten better at sight reading if I applied myself more diligently? And what would that have even looked like anyways? Are there specific t...