So...you're mad because you deleted characters thereby forfeiting your eligibility for some of the Age of Triumph rewards? I can understand that. I'd be mad too. But it does make perfect sense from a database point of view to tie activities directly to the character that played them. Delete the character and you delete it's history with it. The information is no longer relevant after all. Except for these rewards of course but these weren't a thing when the database was created years ago plus the space they'd take up just so you can be given an emblem years down the road isn't worth it for Bungie.