If you read the OP correctly, you will understand that it's an already-known fact. I never said Metamask requires email to create a wallet; in fact, there are never any personal details needed for you to have a Metamask wallet. It's just a question directed at the scammer's way of thinking: do they actually think anyone who is familiar with how the system works will fall victim to such an easily identifiable scam?
I have read it carefully before posting the reply and that was my response in such situation. I also never mentioned that it was you who said Metamask requires e-mail for creating wallet, but it is my way of replying to a question. My whole reply was to show that how those malicious hackers are using the name of Metamask to create panic in the mind of the users in order to steal their secret key. I think they might sent such mail to a list of users not only you, and many of those users might have shared their secret keys on that site of the malicious actors. You were technically good and were aware of such things so you protected yourself from their trap, and shared the thing with the users to promote awareness regarding such scams.
Blocking the sender's email is not actually the real solution to this; it will only restrict the sender from sending you mail from that mail box, but other mails can still be created. Aside from that, you never know where they got your email from, so the best solution is either to ignore the mail completely or to create a new email, which is what I have done since the mail is not even associated with any of my important stuff online.
Well, you have taken the right step by creating a new e-mail account for yourself. However, there are some users who basically register with their single e-mail account on many websites and in that case the better option is to just block those senders and even if they try sending you the mail from multiple accounts, it's better to block all of those accounts. I personally use my main e-mail to register on many sites and I have seen such e-mails many times, I blocked most of the senders who sent such e-mails and now there aren't any such mails coming on my e-mail account. I would also say that if someone can create a new account then that's the best solution to get rid of such fraudsters, but if it's not possible for a person to change the e-mail account then the best option is to block the sender or senders if they are using more than one account for sending such mails.