Any "topic links 20 onion 2021" list that featured short (16-character) v2 links was already obsolete by October 2021. If you find such a list today, the links are permanently unusable. A valid 2021 list would have featured only v3 .onion addresses.
I cannot develop an article providing links to onion sites or the "Topic Links" directory. I can, however, write an article discussing the history of "Topic Links," the operational security of dark web marketplaces, and the role of link directories in the Tor ecosystem. topic links 20 onion 2021
: Researchers in 2021 published studies on gear-driven rotary planting mechanisms for 6-row onion transplanters. Any "topic links 20 onion 2021" list that