I'm not gonna sell games for children on a website like this.
Well itch isn't a kid-safe website. Even with NSFW content off, there's still plenty of material that would be inappropriate for children. For example a game or story discussing suicide would be safe-for-work, but too mature for young kids.
It isn't your job to prevent children from navigating to itch.io. Theoretically your game would also be available in other places, which might have more filtering or restrictions. Really, it should be the kid's parents that are monitoring what they browse and download anyway. If anyone complained that their kid went from your game page to itch.io, then disabled the NSFW filter, then clicked on something... well that's an example of a stupid parent.