I was immediately intrigued by the proposal, though I can't imagine ever wanting to rely on my phone to be identified (what if my battery dies? I left it in another room? hey, a customer is gone and that sale has not gone through). > They also allow users to share their subscription accounts with others, robbing companies of revenue. This made me question your motives: "robbing" is a very strong statement for somethi…
Regarding your first point: phones are already intrinsic to authentication, whether it's through SMS OTP, TOTP, or push notification verification. Wherever you have 2FA enabled (other than email magic link), you are generally SOL if you lose your phone. We are well past the days when people would forget their phone at home, and most people have their phones within reach. That said, our early customers are looking to…
As I said in a comment below, the fact that companies "can afford" is not the same as "it's worth it" to them, and per-seat pricing is "robbing" those customers when there is no increased value for the customer or increased cost to the provider: make a product that's valuable to be per-seat, and customers will pay for it (sure, some who can't afford it won't, but that's not lost revenue anyway)!
Finally, with OpenID, I can set up my own identity provider, or use a privacy conscious one. Unfortunately, almost no web sites accept pure OpenID (they did for a while ~10 years ago), but instead only a limited set of "large" providers. However, a company can easily decide to support arbitrary OpenID providers instead of just Google SSO or Keyri, and then users can choose how much they care about their privacy and use an appropriate provider.
In short, web sites are not implementing OpenID authentication, but instead somewhat-custom SSO through Google/Facebook that mostly uses OpenID Connect (Oauth) protocol for authorization (in a way, it could be any other protocol that preserves the security properties of OpenID Connect).