I was going to mention the support aspect. I believe some TOTP 2FA applications have automatic online backups by default but some don’t and require users to make their own backups. I can only imagine how challenging it would be to deal with users who have locked themselves out of their account due to their 2FA setup.

I had to go through that with itch.io a while back and had to verify my most recent purchases to recover my account. It was nice I was able to get it back but that in itself could be a security concern.