Organisating a directory of websites, or information about websites, by IP address/range is still common. For example, we can see news.ycombinator.com listed here:

https://www.robtex.com/cidr/209.216.230.0-24

https://www.robtex.com/ip-lookup/209.216.230.240

The above directory has been online for at least 18 years.

Here is one I can remember that disappeared:

https://web.archive.org/web/20090907060026if_/http://onsamei...