I have ~1000 accounts, ~200 of which are used for work occasionally. Their 2FA recovery methods vary, and some have no recovery method. I'd like to say my wallet is not large enough for the printed codes, but only about 5 accounts even offer backup codes, considerably fewer than the number of 2FA accounts.
Besides, my last Gmail account for work appeared to be locked to my phone and didn't accept backup codes, and was OAuth master to a number of other accounts.
(For real: I lost access to that Google account permanently when my phone screen stopped working due to an internal fault. It wasn't really a problem and I didn't pursue it fully because I left the job soon after anyway, but the fact I couldn't regain access during that time despite copying the broken phone's content to a new device which successfully transferred the 2FA codes for all other accounts, was striking. It's why I don't use Google for id when there's another option. I tend to use GitHub for id at the moment.)
Besides, my last Gmail account for work appeared to be locked to my phone and didn't accept backup codes, and was OAuth master to a number of other accounts.
(For real: I lost access to that Google account permanently when my phone screen stopped working due to an internal fault. It wasn't really a problem and I didn't pursue it fully because I left the job soon after anyway, but the fact I couldn't regain access during that time despite copying the broken phone's content to a new device which successfully transferred the 2FA codes for all other accounts, was striking. It's why I don't use Google for id when there's another option. I tend to use GitHub for id at the moment.)