I don't think it's that simple. It was useful then because web discoverability was an unsolved problem, and web content was tiny compared to today. A directory sort of fit the need. As the web grew directories became bloated and hard to navigate, search became
more useful.
This is more of a nostalgia or niche link list. It's not the same purpose as yahoo in the 90s.
I think that search engines like Google are unbeatable to find content that we already know about. On the other hand, those lists are great to discover what we don't already know about, such as new topics, etc. Just like the awesome lists on GitHub.
My thought exactly, and also why I don't just search 'latest news' on Google every morning. Human curation is a thing. (not sure how much human curation goes into ooh.directory, but I'm pretty sure they don't use Google's ranking algorithms to surface links)