Hello. I thought I'd make this message for anyone who wants their Neocities site, or parts of it, to have any degree of privacy or doesn't want any archives of their site to be made.
Unfortunately, it seems that Neocities does not want us to give us the right to keep our sites and uploaded files private or for them to be forgotten.
See: "Finally, we sometimes see people trying to use .htaccess for authentication (with usernames and passwords). Neocities is only for sites and information you want to make public, and it is dangerous to use it for private sites! We make backups of your site and attackers can easily find any information you're trying to hide using our archivers. Our goal is to make sure your sites stay up for a long time and persist, not to enforce secrecy zones on your site. If you want to make a controlled access site, Neocities is not for you." (found from FAQ on htaccess files.)
Neocities, I really appreciate the service you guys have given us to express ourselves. But if we really want our sites to stay up, then we will download them periodically and upload them somewhere else if and when disaster strikes, since you have graciously given us the ability to do so. Please don't take away something that's so valuable for everyone, and so scarce on the web today, just because a few of us could be forgetful. If you're not planning to change this, then PLEASE make this fact clearer to the community, so we know to be careful about what we're uploading.