Does verification not work with Google SMTPs anymore due to blanket 250 response?

[im-kent]

Not necessarily the code itself, but to verify emails, the method is to compose an email through the SMTP connection but not send it, and the SMTP server would either respond 250 OK or 550 error (for not found).

However, while doing this, regardless of whether the account exists, Google SMTP responds 250 OK after RCPT TO: [email protected].

Anyone have any insight here?