The main reason folks grab older accounts is to skip the brutal monthly limits eBay slaps on fresh profiles, plus you get instant credibility from existing feedback. You gotta be careful though, most marketplaces are full of scammers selling recycled junk that gets suspended within a week. A solid breakdown of how and where can safely buy ebay seller accounts without getting burned on the handover process is laid out pretty well here
https://gologin.com/blog/buy-ebay-seller-accounts/ . Covers the difference between stealth and business types too so you know what fits your hustle.