Too many services only support a single MFA enrollment. I have a pair of yubikey but don't use them most of the time because most services won't let me registe

Too many services only support a single MFA enrollment. I have a pair of yubikey but don't use them most of the time because most services won't let me register both concurrently, and I'd rather not be permanently locked out if one of the yubis gets lost / contact pins wear out / etc. That said, you're lucky if they support one FIDO2 auth method at all instead of just SMS.