The 2022-03-03 Level1Techs video “Mini Server!!!” showcases a Supermicro mini-server, that does not appear to be available from Micro-Center at all anymore. The inventory status shows as “not carried” rather than out of stock.
I mention this, because A) the video is only about a month old B) Wendell said there might be more content using this server as a platform in the future.