I imagine that $9k ad revenue is a site that had an actual user base. And that the guy taking over the domain is going to just put all ads and no content, like he had on Friendster.com. And if so, the expected ad income is probably much lower.
The WayBack machine shows the redirect to the ad page offering the domain for sale.
https://web.archive.org/web/20231018214628/https://friendste...
So doesn't seem like it was serving ads anyway