ALLOW PEOPLE TO ACCESS OLD USERNAMES!!!

Last year i deleted an old shared microsoft account that i had when i was younger, and i had a copy of minecraft connected to it. however i wasnt aware that after i deleted the account i could no longer get that username back because i had to repurchase minecraft and you guys dont release the users, if i have my purchase ID and proof that the email is infact mine i should be allowed to reclaim my old username, as it is also the username for my channel on youtube and everything else i use. its entirely unique to me and its extremely frustrating and quite frankly dumb that i cant have MY username back.