3/ Let's now consider what makes hyperlinking explicitly social.
Virtually every website has a hyperlink. Most of the time, these hyperlinks reference other pages on the site.
But they can do something else: reference pages on OTHER sites.
This is important because visitors to your website don't need to be siloed to your website. They can now become aware of a much wider world of creativity.
I understand that you may not want to moderate abuse. But that's just absolving yourself of responsibility.
If you're going to let your instance be open for all registrations, then that means moderating for everyone who joins—especially for people targeted for abuse.
Don't want to moderate? Then close registrations to your instance.