Thinking of reasons to not do this though, it's effectively impossible to content moderate, at least not without building a database of all the content you don't want to host.
That's even worse. The issue is not that you have the bytes, it's that users see the content on your site. The less control you have the more difficult it would be to meet legal obligations surrounding user generated content.
The deal made years ago in law in the US (and followed around the world) is that websites are not liable for the user generated content that they make available, as long as they remove it if requested for legitimate reasons. These two components go hand in hand. If a website is unable to remove content, it's effectively liable for that content. This basically breaks the web as we know it today.