I haven't logged in for a while but still do Arduino projects. Unfortunately the enhanced Forum login procedure now seems to require a mobile phone, a QR code scanned and app to get started? I don't use mobile phones which are too easy to lose, hack and have personal data compromised.
I seem to be able to share this message now, but suspect my account will auto delete. Same with other members I suspect and perhaps the site admins need to understand why? I haven't uploaded sketches and losing my account would be no big deal, but reminds me not use third party servers to save and store work.
If a login authentication code had been sent to the email address registered to my account, then login and authentication from a PC would have been possible.
Not to my knowledge. When I need to login, it does not require a two-factor authentication.
There is a dedicated section (Website and Forum - Arduino Forum) for questions/comments on the website; you can move your topic there if you feel it's more suitable.
I moved your topic to a more appropriate forum category @Voxmagna.
I don't think so. I have a test account without two factor authentication (2FA) set up. I just logged into it without any problems. The website does periodically display a page when I log in that recommends setting up 2FA. However at least the last time I saw it (it didn't display on this login), it was completely optional.
I don't know whether it was done here, but UI designers often employ a technique when they want to strongly persuade the user to take an optional action. They make the button/link for the action they want you to take very visually prominent and inviting and the button/link for declining to take that action fairly bland. If that is the case with the 2FA recommendation page, you might have simply missed the option to decline to set up 2FA.
Please provide a detailed description of what makes you suspect your account will auto delete.