Honestly, the only way I see forward is FIDO with dirt cheap NFC cards as keys. Need to log in to somewhere? Get the card from your wallet and touch it to your phone/laptop. It has to be cheap enough that for any company with paying customers it makes more sense to physically mail them a card if they don't already have one than to support any alternative auth methods.
Most services won't even need a second layer of auth, if someone steals your wallet - do they really care about your reddit account?
Most services won't even need a second layer of auth, if someone steals your wallet - do they really care about your reddit account?