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 deploy Keyri as an option parallel to password-based auth, which, while not ideal, is a smooth way to transition their users to a better UX that just happens to be more secure.
Regarding account sharing: agreed that the "robbing" language is harsh and should be toned down. That said, it is a problem that deserves a solution. For example, there are companies like data providers that charge businesses hundreds or thousands per month for access to their platforms, and they face massive account sharing issues from these businesses that can totally afford to pay for all of the seats they need but are not willing to pay because they don't need to - they can just share accounts among their employees. At the same time, I'd argue that any account sharing, even if it's for a $5/month streaming platform account, is unethical and a violation of TOS - companies should have access to tools that definitively prevent these violations. They currently already try to stop account sharing through IP logging, cookie tracking, etc., but those methods are not as reliable as changing the auth mechanism altogether to something like Keyri, in which credentials are not free-floating strings that can be passed from one person to another.
Regarding OpenID: OpenID providers (Google, FB, etc.) don't see your private keys, but by registering and logging in on various services through them, you are giving those platforms yet more data about yourself. That is why these platforms provide OpenID auth services for free. This privacy threat is nebulous, but privacy-conscious people like myself don't use OpenID for this reason.
Edit: an article on OpenID privacy issues from people who know more than me: https://people.inf.ethz.ch/basin/pubs/asiaccs20.pdf. Excerpt: "s. Unfortunately
OpenID Connect is not privacy-friendly: the identity provider learns with each use which relying party the user logs in to. This necessitates a high degree of trust in the identity provider, and is especially problematic when the relying parties’ identity reveals sensitive information"
Regarding account sharing: agreed that the "robbing" language is harsh and should be toned down. That said, it is a problem that deserves a solution. For example, there are companies like data providers that charge businesses hundreds or thousands per month for access to their platforms, and they face massive account sharing issues from these businesses that can totally afford to pay for all of the seats they need but are not willing to pay because they don't need to - they can just share accounts among their employees. At the same time, I'd argue that any account sharing, even if it's for a $5/month streaming platform account, is unethical and a violation of TOS - companies should have access to tools that definitively prevent these violations. They currently already try to stop account sharing through IP logging, cookie tracking, etc., but those methods are not as reliable as changing the auth mechanism altogether to something like Keyri, in which credentials are not free-floating strings that can be passed from one person to another.
Regarding OpenID: OpenID providers (Google, FB, etc.) don't see your private keys, but by registering and logging in on various services through them, you are giving those platforms yet more data about yourself. That is why these platforms provide OpenID auth services for free. This privacy threat is nebulous, but privacy-conscious people like myself don't use OpenID for this reason.
Edit: an article on OpenID privacy issues from people who know more than me: https://people.inf.ethz.ch/basin/pubs/asiaccs20.pdf. Excerpt: "s. Unfortunately OpenID Connect is not privacy-friendly: the identity provider learns with each use which relying party the user logs in to. This necessitates a high degree of trust in the identity provider, and is especially problematic when the relying parties’ identity reveals sensitive information"