You cannot stop people from being attracted to minors. Making something illegal doesn’t magically remove feelings, nor does it magically prevent people from doing it. The threat of prison has never stopped prisoners.

There’s a decent amount if evidence that it’s at least partially a fetish rather than a sexuality, so people are more likely to become paedophiles if they’re exposed to things that make them associate children with sex (including being assaulted as a child), and their attraction to children becomes stronger the more they’re exposed (so people who download some CSAM are more likely to want to download more and more likely to escalate to doing things in real life).