>it would be important to think about why OpenID/Persona didn't catch on or the already-supported x509 key

Why did SIM chips take off? Why did credit cards with smart chips take off? These both embed private keys. Even desktop computers are now embedding private keys in their motherboards.

Clearly, something is missing from your analysis.

The private key there is only an implementation detail, though. The reason people don't care about it is because in the case of a SIM card you can get a replacement SIM while keeping the same phone number (which is what people really care about), and in the case of a credit card where a premature replacement might involve a change of credit card number

- for one-off payments it doesn't matter anyway, you just start using the new card and that's it

- and for recurring payments all businesses already need to allow for updating your credit card details because credit cards regularly expire anyway, so having to possibly manually update all your recurring payments might be a bit tedious and annoying, but it's certainly no impossible, out-of-the-ordinary task

> Clearly, something is missing from your analysis.

And yet you are unable to say what or offer relevant examples. Do you login in to websites using the key on your phone's SIM or your credit card? Both of those are amusing because they're bot not only irrelevant to the scenario in question but also something people use because that's what they were given, not something they sought out.

Okay, if you really think this is the case, then I understand the argument.

I mean, you're the salesperson, sell the benefits — to the average person, how does this proposed system make their life better?

It's about competition. You remove user lock-in and thereby create a market of competitors seeking to win users from each other.

Okay, so what does that mean for the normal person? They're going from trusting Google to trusting another company which costs more, or holding their key themselves with the knowledge that they'll be locked out of all of their accounts if they lose it or are compromised. I understand that you have a financial benefit if they sign up but what part of that says “here's a benefit to you which is worth paying $$$ for!” to a normal person?

You're mixing multiple issues up. Passwords and private keys are exactly equivalent in the possibilities of loss or compromise (and recovery). So we're not touching any of that here.

> what part of that says “here's a benefit to you which is worth paying $$$ for!” to a normal person?

You get to keep your contacts even if you get booted off the platform (or your contacts do).

And it doesn't cost anything.