what if I have my own domain and I have my own email like [email protected]? So you won't allow me to play? Bad idea.
Also the reason why people make fake mails is because we can't use the same email for multiple accs.
Well if your intention is to forbid multi accs then RIP this thread
old account is already enabled (only new accounts would have this requirement)
not so difficult to do, only more time consuming, I do not see problem in several acc (you can create multiple emails real)