tbh I have only ever seen a couple in an omnipresent sidebar in my lifetime. The vast majority I encountered around then and earlier were just in the "about" (or possibly "links") pages of people's websites, and occasionally a footer explicitly mentioning "webring".

Also if you squint hard enough, they're massively more common now. They're just usually hidden by adblockers because they're run by Disqus or Outbrain or similar (i.e. complete junk).