The Kademlia network (eMule, Kazaalite, etc), did indeed use a global P2P Distributed Hash Table, to resolve which IPs hosted which content, which the torrent protocol also does ... some of:

Unlike the mainline torrent protocol, Kademlia's DHT (like the modern-day Tribler DHT), also resolved filenames to content, allowing in-app search.

With torrents, one needs to consult a DHT crawler, or an index site (which sucks; centrally operated sites are fragile, compared to DHTs), whereas eMule & more contemporarily Tribler, have two layers of DHT, enabling decentralized search without relyiance on someone having created a listing at some particular site & that site being online to search its index.

eMule was introduced in 2002, which is again NOT THE 90s. Napster also uses a very different protocol, without any of the distributed file sharing. With P2P like Napster, soulseek, and DirectConnect you downloaded a complete file from one person only. Once you had it and could share it, someone could get it from you. But downloading bits of the same file from multiple peers at once was not a thing until after BitTorrent's release in 2001.