Lets say I live in the United Stats for 6 months out of the year, Spain for 2 months, Japan for 2 months, and Brazil for 2 months. Based on this design, I need servers to exist in 4 different regions.
Why?
If I'm on anarchist.nexus, I can browse lemmy.ca. I can make a local community on anarchist.nexus for my town. A user from feddit.dk can then browse and chat with me. Maybe they lived there? Maybe they'll be back for a month in a few weeks! They can post about that in my extremely localized community.
If we switch that to items - that user from feddit.dk can't post a listing to my local community, can they?
Why is it determined by a server region? Why isn't it, for example, a server dedicated to listings about sports memorabilia? Do I care where the signed baseball I want to buy is? Do I care where the buyer is from that wants my tennis racket I've put up for sale?
What relevance is the region to the server? The relevance is to the listing.