One of the legitimate reason users create Alt account is because they can't afford 50+ BTC to have the privilege to change username. I would love to change my username to something more unique and shorter but the best option now is to create an alt account but I'm scare not to get red tagged for owning one that's why I'm still using this account.
You are allowed to create a new account if you want and stake it as your alt account from your main account.You won't get red tag for doing this until you are doing shady things which are not trusted by DT members.Literally you won't get tagged until you are cheating same campaigns with multiple accounts.