I use the yubikey for OpenPGP (with SSH) and I took care to generate the keys on my computer then back them up appropriately. I can restore to any new yubikey q

I use the yubikey for OpenPGP (with SSH) and I took care to generate the keys on my computer then back them up appropriately. I can restore to any new yubikey quickly (tested). It's also easy to get two yubikeys and have a backup ready to use immediately. As to U2F, there is always a backup method (usually TOTP generated by Google Authenticator, and additionally recovery codes).