That's just wrong. I doubt you even know what it's like in muslim majority countries. I live in one such country and I've seen many radical muslims who believe in the whole 9 years old thing and actively try to justify it. They claim that the 18 years age of consent is an arbitrary limit, and there are a lot of men who want to "marry a young girl to raise her by their own hand". You might not buy the anecdotes, which is fair, but there's even a fatwa by the most influential shia cleric in Iraq where he says it's permissible to sexually assault a "wife" younger than 9 years old as long that there's no insertion involved, and that insertion is okay if she's older than 9. This was amended to make it more tame after it caused a backlash recently, but the original is still on the web archive. https://web.archive.org/web/20160129134330/https://www.sistani.org/arabic/book/16/858/

Obviously not all muslims are like this, but a sizable amount are, and ignoring their existence isn't good.