I don't know anything about the site you linked, but at face value, that article is absolutely awful. (Is it satire?)

For example, the point at the end saying the book celebrates a guilt-free genocide. Not the point at all! OSC wrote the entire rest of the series about his main character grappling with the guilt of what he did.

That's...an interesting take. The character they're talking about didn't appear in the first book. She was introduced later in the series: https://en.wikipedia.org/wiki/Jane_%28Ender%27s_Game%29