If you are on Apple ecosystem, iCloud can sync. Other password managers like 1Password can also be used to store your passkeys. If none of the above, you can always set up a physical security key and leave it at home.
IMO if you're reading hacker news, you're fully capable of setting one up and leaving it in a safe locale for recovery.
IMO if you're reading hacker news, you're fully capable of setting one up and leaving it in a safe locale for recovery.